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archive:science:rqmsgs_t

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Msg#: 1846                          Date: 10-05-93  12:54 
From: Richard Quick          
  To: David Tiefenbrunn                             
Subj: 10KVA Tesla Coil 

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DT> Where are you running this thing now, out of curiosity? DT> Don't the neighbors complain about the RFI? DT> Do you have any pictures or .GIF files of this unit in DT> action?

I run either in the garage for low power tests, or set up outside in the back driveway for the real high powered stuff. I have had no RFI complaints, but have had complaints about the noise: the spark gaps sound much like an unmuffled chainsaw run flat out, wide open. I made peace, and am allowed to fire up until 10 P.M. with a days notice. But no more 2-3 A.M. testing…

> I have used forced air cooling (ozone city) with good results > up to about 5 KVA. RQ

DT> Have you tried cooling the air before it is blown into the DT> spark gap? You could run the air (I'm assumeing that your DT> using an air compressor) through a coil of copper tubing in DT> your ice bath. The best part is when the air expands as it DT> is blown into the gap, it will cool further. (basic physics DT> of gasses type stuff)

I cool using forced air from a 220V industrial shop vac motor in my old set of gaps, the new gaps are quenched by air blast from a 3.5 HP air compressor. The problem is the CFM of air flow required is so large that I don't think pre-cooling is pratical. It would require another design modification. The expanding air alone works pretty well. The real advantage to high speed forced air is that it not only cools, but it physically disrupts the high voltage arc, assisting the rotary in making the break.

Your idea for a forced air cooled rotary gap was excellent. The only problem I see is in engineering the units to specs close enough to get excellent performance and safety. My rotors are dynamically balanced to 5000 RPM, and break rates need to be 450 BPS or better for good operation. In designing a rotating break I try to keep the mass as low as possible on the rim: when they come apart they resemble an explosion, with lots of hot shrapnel and plenty of arcs and sparks!

> The research goes into several directions…Anybody know how > to get lightning to excite a gas laser tube? RQ

This was misunderstood by severl people. Specifically what I was wondering about was the possibility of using the oscillator output (which is similar to lightning) to excite a monopolar (one wire input) gas laser tube.

DT> Do you know what the mix is in a standard NeHe laser tube?

No. I am not an expert on lasers. But I am more than willing to learn. I am open to input from anybody with experiance.

RQ> … And if all else fails… Put another megavolt through RQ> it. DT> With your equipment, it sounds like you actually could…

Absolutely, positively. Though I can't figure out how to make a RF voltmeter that would not be utterly consumed by the output of my machines. My guess is between 3 - 5 million volts output with the setup we have been discussing.

As for proof. Yes, I can supply proof. I have some still photos taken at about 3600 watts which are very impressive. But as my work progressed I switched over to recording the experiments on video tape so I can analysize the tests in the safety and comfort of my living room. If anybody writes me I will happily provide a two hour video tape in exchange for: One blank (high quality) VHS tape, a postage pre-paid return mailer, $10.00 to pay for my time and effort in seeing that you get a high quality, two hour, recording of my work. Note this offer is not made on my behalf to make any money, and I am not resposible for anybody's safety should they decide to replicate any of the experiments I perform. I will send a glossy print for $1.00 and a SASE.

Richard T. Quick II, 10028 Manchester Rd., Suite 253, Glendale, Missouri, 63122, USA

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Msg#: 1971                    Date:10-09-93  16:29 
From: Richard Quick             
  To: Guy Daugherty                 
Subj: 10KVA Tesla Coil 

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GD> I'd say if they're working that well for you, they're hardly GD> junk. Is there, uh, any point to this stuff, or just GD> blasting electrons across the ether?

Yes, there is a purpose. Actually more than a few.

High power particle accelerators is one. The typical linear accelerator of the 30's and 40's were RF powered. They abandoned the coils as they were not sufficently frequency stable, and the output was damped as opposed to continous wave. But, a book was published last year: NICKOLA TESLA ON HIS WORK WITH ALTERNATING CURRENTS AND THEIR APPLICATION TO WIRELESS TELEGRAPHY, TELEPHONY, AND TRANSMISSION OF POWER. Leland Anderson, Sun Publishing, available through 21st Century Books, P.O. Box 2001, Breckenridge, CO. 80424.

This work is the result of research into the files of several law firms dating back to around 1915. Tesla was called to give depositions for three days to prepare for patent trials against the Marconi Company. Tesla clearly documented priority in frequency stablized continous wave signal production and radio signal transmission (and reception) on multiplexed circuits as early as 1891. All of Marconi's patents pertaining to radio were overturned by the U.S. Supreme Court in 1942 or 1943. The key to this is that Tesla's work in this area was extremely advanced, and most of it has yet to be applied to high powered accelerator work. His systems of continous wave RF current production with very high potentials is easily adapted to small, high powered, linear particle accelerators. The peak powers of his Colorado Spings machine (built, tested, and documented in 1899) exceeds all but the largest accelerators in existance today. By the way, the Tesla system is continous, and the modern systems are pulsed. The misunderstanding is damped vs. undamped wave production. The machine is capable of both, though the famous photos were taken when the machine was set up to produce damped (disruptive) waves. I don't think anybody really understood what Tesla was doing, certainly he never clearly explained it until I read the work above.

In addition to this, a moderately sized machine should be capable of doing research into power transmission through earth resonate ground currents at frequencies under 30 khz (see document above). Later Tesla realized the particle accelerator potential of the machine and designed a power head for a particle beam weapon using the magnifier circuit as the signal generator. Lasers were not invented yet when Tesla died, but I believe a low impedance coil system can supply enormous peak powers to gas laser tubes.

The Maser is a derivitive of this line of investgation, though the frequencies of operation are much higher than can be supplied from a coil system, the idea is exactly the same. Use a tuned gas laser tube as a cavity resonator excited by the RF output of the coil system.

Then there is ball lightning research…

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Msg#: 125                           Date: 10-09-93  22:35 
From: Dave Halliday       
  To: Richard Quick            
Subj: 10KVA Tesla Coil 

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>a two hour video tape in exchange for: One blank (high quality) 
>VHS tape, a postage pre-paid return mailer, $10.00 to pay for my 
>time and effort in seeing that you get a high quality, two hour, 
>recording of my work. Note this offer is not made on my behalf to 
>make any money, and I am not resposible for anybody's safety 
>should they decide to replicate any of the experiments I perform. 
>I will send a glossy print for $1.00 and a SASE. 

RQ>Richard T. Quick II, 10028 Manchester Rd., Suite 253, Glendale,

>Missouri, 63122, USA 

Two comments:

1) - What IS your monthly electrical bill

2) - The $10 is in the mail Monday

have been a wee fan of Tesla for a looong time - talking with some people now about maybe building a BIG one out in Seattle - have done a few small ones

b QMPro 1.51 b 10… 9… 8… 7… 6… (Bo Derek getting older).

-!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546)

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Msg#: 2001                           Date:10-10-93  16:33 
From: Richard Quick                   
  To: David Bearrow                    
Subj: 10KVA Tesla Coil 

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DB> How did you go about winding your coil? What are the specs? DB> And how much did it cost?

The first step in winding a coil is to select a coil form. The coil form should be a low loss material (we are talking RF losses) like polyethylene, polystyrene, or polypropylene: but the most common material is PVC plastic drain pipe (thinnest wall is best) which is high loss. I used a section of PVC thin wall flume duct.

Ratios of coil height to width are important. Small coils work best with aspect ratios (height to width) around 5:1 - 4:1, larger coils (over 8" diam.) have aspect ratios around 3:1. Now we are talking about the actual winding length here, so allow an extra inch or so of coil form on each end. Determine the length required and cut the ends square.

The form must be sanded smooth of surface imperfections, dried thoroughly, and if PVC is used, it must be sealed. A good sealer is polyurethane, another is two part epoxy paint. By sealing the surface of the PVC before you wind on wire you can negate the excessive losses in PVC plastic coil forms. If necessary the coil form may be sanded after the sealer had dried.

The coil should be wound with good quality magnet wire. I use double Formvar enamel coated magnet wire. Magnet wire gives you maximum inductance. A coil should have over 900 turns, but not too much over 1000 turns. There is a little leeway here. Select a gauge of wire which will allow the aspect ratio and number of turns to fall within this range.

I plug the ends of the coil form and run a dowel through a center hole so that it will spin. I set up the wire spool on one end of a pair of sawhorses, and the coil form on the other end. I wind the wire on by hand, making sure the windings are tight, smooth, and even. I use a dab of hot glue or tape to hold the first turns in place, and make sure to leave a tail of wire at either end.

Once the coil is wound, it is sealed to prevent corona leakage and breakdown. I use the same sealers mentioned above. Coats of sealer are applied until there are no ridges and valleys in the wire. In other words the coats must build up until the wire is completely imbedded in sealer.

The wound, sealed, coil is capped at both ends with plexiglas plates glued down with epoxy. I cut circles out of plexi sheet that is about the same thickness as the coil form. I rough up the surface around the edges to give the epoxy a bite. One small hole may be drilled into the bottom end plate to allow the air pressure to equalize, but under no circumstances should any other holes be drilled. The wire is never allowed inside the form.

I have numerous coils, my largest coil has specs as follows: 10.5" O.D. thin wall PVC flume duct, the coil form is 34" high. The coil is wound with #21 magnet wire, 1024 turns, actual winding length is 32", aspect ratio 3.05:1. The coil is sealed with eight coats of polyurethane on top of the wire and five coats under the wire so that the wire is not in contact with the PVC but is suspended in sealer.

Coils take time more than anything to construct. I suppose the material cost for my 10" coil is around $60.00. Smaller coils are cheaper of course. What can be expensive is putting together the rest of the oscillator components. Things like HV pulse capacitors, xfrmrs, and power controllers like variacs. Beginners can usually start with a few old neon sign xfrmrs, make some caps (homemade salt water caps are very cheap) or buy some used, and fire a small coil for under $150.00 from start to finish.

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In a message of <Oct 09 20:51>, Richard Quick (1:100/4) writes:
A twenty-two megawat continuious fire gas laser…

BD> I just picked up this thread a week ago, your recent postings BD> are saved to a file…This is very interesting!

MF> 22 MW is your input, with typical gas laser efficiency you'd MF> be lucky to squeek a (one) measly MegaWatt out. Just enough MF> to cut through armor at a few inches per second, or mabey a MF> foot of steel. Don't know about lunar soil. Some gasses MF> don't scale well to high powers, CO2 would probably be MF> the best candidate.

>I kind of thought CO2 was the way to go, but I was not sure. I

have not had much experience with high powered gas lasers,
though I did build a ruby rod laser in high school powered by a
xenon flash tube. I can't find the rod anywhere now…

BD>CO2 is a good choice for high power. I'm not sure which BD>transition level for CO2 is used for lasing but I could find BD>out.

>I have a feeling that with a properly designed system though,

the efficiencies could get considerably greater. My assumption
is based on some experiments which show that RF excites gases
much more easily than high voltage, high currents, or both.
Telsa went on and on about the advantages of using RF when
energizing gasses.

BD> A Soviet researcher named Kapitza developed RF devices with BD> plasma temperatures high enough to fuse hydrogen! They used a BD> cylindrical resonant chamber driven by a room full of tuned BD> circuits, the high temperature was observed in a corona BD> discharge along the axis…I guess it went on the back burner BD> along with the tokomak.

BD> Hmm…stick a CO2 filled tube in a properly sized RF BD> resonator… a few mirrors, heat sinks…

BD> I wish I had your original post. :-(

BD> ! Origin: Wendell Woodworking BBS(508)544-2402 (1:321/154)

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Msg#: 2097                           Date:10-13-93  00:46 
From: Richard Quick                 
  To: David Bearrow                 
Subj: 10KVA Tesla Coil 

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» The coil should be wound with good quality magnet wire. I use » double Formvar enamel coated magnet wire. Magnet wire gives » you maximum inductance. A coil should have over 900 turns, » but not too much over 1000 turns. There is a little leeway » here. Select a gauge of wire which will allow the aspect » ratio and number of turns to fall within this range.

DB> Did you calculate this so that the capacitive reactance DB> equals the inductive reactance? I understood thats what was DB> so interesting about Tesla's coils.

No. The balancing act that you are referring to occurs in the primary tank circuit. High voltage pulse discharging capacitance (capacitive reactance) is made to balance off the heavy primary coil (inductive reactance). The primary coil is made to very low resistance; like HEAVY cable, strap, or soft copper water pipe. The inductive reactance is "canceled" by the capacitive reactance, and a very low resistance "tank" is formed where heavy currents can oscillate with low loss. In order to excite the tank circuit, high voltage feed lines are brought in to charge the capacitors. Voltage rise in the capacitors (as they charge) breaks down the main system spark gap, and bang, the tank fires. Currents of hundreds of amps, with voltages in the thousands of volts, ring through the Tesla Tank Circuit.

The energy delivered can easily reach peak powers in the megawat range. Since the main system spark gap fires hundreds of times per second, these high peak powers are, for most practical purposes, continuous. This primary circuit energy is transmited through inductive coupling to the Tesla Secondary.

The secondary coil that I described in the quoted post is NOT a balanced coil. On the contrary, this coil is pushing the extreme of several design limits in the quest for more efficient power processing. The secondary coil, wound as I instructed, results in a very high inductance coil; but it has a significant internal capacitance and resistance due to the closeness of the windings, the length of the wire, and the number of turns.

The high inductance makes the secondary effective. The higher the inductance, the more energy can be absorbed from the primary tank circuit.

Resistance and internal capacitance limit the Tesla secondary for obvious reasons. Current, especially RF current, reacts poorly to resistance, which gets worse in small diameter wire. Internal Capacitance in a coil also reduces throughput, as the capacitance in the turns of wire slow the current peak.

Designing a potent Tesla secondary balances the maximum inductance (a positive factor) against the resistance and internal capacitance (negitive factors). It takes into account the need for "critical coupling" between the primary and secondary (for good energy transfer), resistance of the wire, internal capacitance between turns, and the breakdown voltages of the construction. The design given is well researched and proven.

> BUT THE COIL IS UNBALANCED!!! YOU SAID SO ABOVE!!!

Yes, it is VERY unbalanced. Yes, the Tesla circuit depends on balance for maximum efficiency. The high inductance of the secondary is balanced by the addition of a large (even huge) top capacitance. Donut shaped dischargers, called toroids, are used as a large capacitive air terminal. This air terminal capacitance "unloads" the secondary, and allows for current flow through the high inductance coil. The secondary coil, as I instructed, will not function well without an effective discharger; a capacitive reactance to balance it. Without it the coil will not survive much input energy and will self destruct. We have just pushed the limits with modern plastics in 1/4 wave Tesla oscillators.

Back to the primary; the circuit is tuned. By changing the location of the tank circuit "tap" connection to the primary, the frequency of the circuit is altered. The more turns, the lower the frequency. The secondary coil acts like an antenna. This wire when excited by the primary, vibrates electrically, and produces a quarter wave signal. The frequency is primarily a function of wire length and the capacity of the discharger. The primary and secondary are both adjusted to operate at the same frequency. So there is a lot of balancing going on.

By the way, I make my toroids out of 4-6" ridged flexible black polyproplyene drain pipe. I make a circle and mount some cardboard or thin masonite in the center, then cover the thing with aluminum plumbers tape, and foil glued with adhesive spray.

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Msg#: 2135                           Date:10-14-93  10:57 
From: Richard Quick                
  To: Bud Davis                    
Subj: Re: 10kva Tesla Coil 

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BD> CO2 is a good choice for high power. I'm not sure which BD> transition level for CO2 is used for lasing but I could find BD> out.

RQ> Please check into it and let us know what turns up.

>I have a feeling that with a properly designed system though, >the efficiencies could get considerably greater. My assumption >is based on some experiments which show that RF excites gases >much more easily than high voltage, high currents, or both. >Telsa went on and on about the advantages of using RF when >energizing gasses.

BD> A Soviet researcher named Kapitza developed RF devices with BD> plasma temperatures high enough to fuse hydrogen! They used BD> a cylindrical resonant chamber driven by a room full of BD> tuned circuits, the high temperature was observed in a BD> corona discharge along the axis…I guess it went on the BD> back burner along with the tokomak.

I really feel that there is a lot of uncovered work in areas such as this. The publication I refered to last week (A transcription of a legal deposistion Tesla gave in 1916, over a period of three days) is only a year in print. Using some of the ideas that Tesla presented in this deposistion in work such this has not been done.

BD> Hmm…stick a CO2 filled tube in a properly sized RF BD> resonator… a few mirrors, heat sinks…

Yup, very close to my thoughts. Tesla states that low pressure gas, being highly conductive to RF, can be used as the actual resonator. So take a properly sized resonator, fill it with CO2, a few mirrors, heat sinks…

The actual resonator can be the laser tube, and losses can really be cut down. This is exactally how a MASER works, but needs to be scaled up for low frequency work. I have been wondering about the addition of a short coil to the resonate chamber to bring the frequency down, thereby keeping the size of the resonate chamber under control.

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Msg#: 2138                           Date:10-14-93  16:53 
From: Richard Quick         
  To: Bud Davis                
Subj: 10KVA Tesla Coil 

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I would also be very interested in the source material for the information you relayed on the Russian RF work. Experiments of this nature (using RF inputs to excite tuned resonators) is exactly along the line that my future work will be heading.

I don't know how much of this thread you were able to pick up in a week (I have seen a lot of posts indicating new boards getting this echo in the past week) but I am currently running and improving very high powered equipment. Experiments of this nature are not at all beyond my means. I have all of the power controller circuits, the capacitors, and the HV xfrmrs. I am developing a new liquid cooled, air blast gap to run in series with my rotary, and I have plenty of coils, both primaries and secondaries.

I have constructed and fired small Tesla Magnifiers in the 2.5 KVA power range, and feel (like Tesla did) that the magnifier circuit is a clear and away breakthrough in RF power processing efficiency. A properly designed and constructed Tesla Magnifier system easily achieves 70% efficiency, and can be brought up to over 90% efficient in larger systems. They will produce and process damped and undamped (continuous wave) signals depending on the setup and power supply. The currents and voltages this circuit will handle are nothing short of mind boggling.

The Magnifier is designed specifically to drive a 1/4 wave resonator, whether it be helical (coil), coaxial, or cavity, makes no difference. I doubt that the Russian was using a large magnifier to drive the resonator in the experiment you mentioned. James & Kenneth Corum (PhDs) did not publish the mathematical treatise of the Tesla Magnifier until just a few years ago, and until the treatise was published, nobody was able to get the free resonator to function properly as part of the lumped, tuned circuit. These problems have been worked on and resolved by very few people since. I can count myself as one of the half dozen or so who have publicly documented success.

My best guess is that the Russian was using a large tube powered RF signal generator to drive a coaxial resonator. I think that if the experiment were redesigned, it could be done much cheaper, at much higher powers and efficiencies, with a Tesla Magnifier driver circuit. Tesla went on and on about this stuff too, nobody listened then, and few listen today; hell, people ask me all the time why I chase such "impracticalities". They don't understand that Tesla was so far ahead of his time that we still haven't caught up! My guess is that we stand today where Tesla stood in 1898, as far as RF power processing efficiencies are concerned.

But photos or data from the Russian experiment would be invaluable for any work in this direction. What did he use for a transmission line? How did he introduce the signal into the resonator? From having done a little work with helical resonators to produce large voltages at very high currents, I realize technique is half the battle. Any additional information on this work would be appreciated.

As for what you missed, well it can't be as much as what is most likely still to come. Stay tuned!!! And feel free to ask about anything you don't understand.

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Msg#: 1981                          Date: 10-16-93  18:39 
From: Richard Quick         
  To: Ron Beam                           
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ >On Oct 10 16:33 93, Richard Quick of 1:100/4 wrote:

>Coils take time more than anything to construct. I suppose >the material cost for my 10" coil is around $60.00. Smaller >coils are cheaper of course. What can be expensive is >putting together the rest of the oscillator components. >Things like HV pulse capacitors, xfrmrs, and power >controllers like variacs. Beginners can usually start with a >few old neon sign xfrmrs, make some caps (homemade salt >water caps are very cheap) or buy some used, and fire a >small coil for under $150.00 from start to finish. RQ

>Richard, do you know what frequency (if not 60Hz) and voltage >should be used for a coil such as you mentioned?

Frequency and voltage entirely depend on the aims of the designer/builder. Since none of these systems are purchased (nearly every component handcrafted) they can be built to nearly any specification desired (within reason). Frequency, input & ouput voltages, current, and impedance are just some of the variables. The idea with a Tesla coil system is to covert 60 cycle line current into RF with very high efficiencies. My 10" secondary coil has a natural 1/4 wave resonate frequency of 132.5 KHZ. I use a power distribution transformer run backwards (put 240 in and get HV out) to step up my line voltage to ~20,000 volts. This input RMS voltage is converted into RF (say 132.5 KHZ) by the Tesla Tank Circuit. The high frequency conversion is achieved as a property of capacitve discharge through a coil (tuned oscillating circuit). The main system spark gap acts as a high voltage switch which allows the capacitor to charge over a period of time, then discharge nearly instantaneously. Because of the pulse discharge, the RF generated in the tank circuit has much greater peak power than the HV feed line from the step up transformer. The grounded secondary coil receives the EMF from the primary and converts the energy back into electricity (air core RF transformer). Since the secondary coil has a much greater number of windings the voltage is stepped up considerably.

> What does the coil do (or look like) when you turn it on?

A 1/4 wave Tesla coil generates very long RF sparks that resemble natural lighting in many aspects. These sparks do not need to strike a grounded object but can terminate in air.

>What can a person do with such a device once constructed? Does >it have any practical purpose other than to amuse your friends?

I first began to build small 1/4 wave (spark generating) Tesla coils for fun. I loved the light show, and so did my friends. As I gained experiance in building coils I realized that most of the "plans" were full of inaccuracies. I began to design my own systems to increase efficiency. As my interest and experiance grew, I discovered more advanced coil systems that Tesla designed (the Tesla Magnifier) and began initial research into other areas: particle acceleration, lasers, wireless power transmission, and particle beams. I am planning on making a very serious study in these areas in the next few years.

Dave Archer is a painter in California who uses a Tesla coil to electrically spread paint. He places his canvas on a grounded plate and directs the Tesla discharge over it. The resulting paintings are regularly featured as space backgrounds and hanging art on Star Trek TNG, Omni Magazine and several other publica- tions, as well as private collections. Tesla coils were also used in the time travel scenes in both Terminator movies, and are re- emerging in the special effects industry because they photograph well and the sparks are more realistic than computer generation or animation.

Two years ago a man (I don't have his name handy) was issued a patent for a thermo-couple using a Telsa discharge.

Tesla coils were used in the first induction heaters, and were employed medically for the treatment of arthritis and other joint and muscle problems. The same coil could be adjusted to generate sufficient voltage to produce X-Rays, and as such a Tesla coil was a standard medical instrument in Dr's offices in the early 1900s. Nearly all of the first high quality X-Rays were produced with Tesla driven X-Ray tubes until the 1930's. The first self cauterizing "electric scalpels" were electrified with a Tesla coil.

A Tesla coil is in your monitor (flyback transformer). Tesla coils were also an important part of the first radio transmitters. My feeling is that the Tesla coil has a major place in modern physics, but has not been fully evaluated.

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Msg#: 1983                        Date:10-16-93  21:30 
From: Richard Quick                 
  To: All                           
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ This thread seems to be getting a lot of attention and responses. I will try to give some basics here, and answer a few questions.

The modern 1/4 wave Tesla coil (sweet and simple, though there are other configurations) is an oscillator driven, air core resonate transformer.

The oscillating tank circuit drives the secondary coil. The tank circuit consists of pulse discharging capacitors, air gap (break) and the primary coil. In my previous post I said the setups are very flexible, so I will focus on specs for the 10KVA coil.

The primary coil is wound from a single 100' length of 1/2" soft copper water pipe placed on plexiglas stand off insulators. The inside turn starts at 14" in diameter, and the turns wind outward to form a flat pancake spiral, like the grooves on a phonograph record. The outside turn is 36" diam.. There are a total of 15 turns in this coil, spacing between turns is 1/4".

There are many ways to place the gap and capacitance in the tank circuit. I like the "balanced" circuit Tesla developed in Colorado Springs for his monster machine. In the balanced circuit the capacitance is divided into two equal parts and placed on the ends of the primary coil. The gap is placed across the HV feed line feeding the caps.

I own two .1 mfd 45 kvac pulse discharging capacitors. These two custom commercial units were purchased to supplement my 14 homemade polyethylene/aluminum flashing/mineral oil units rated at .02 mfd 10 kvac pulse. With the 10 KVA coil I use these two commercial "caps". In the balanced circuit the capacitance is run in series with the primary, so the actual operating capacitance is only .05 mfd..

I connect one cap to the inside turn terminal of the primary. The second cap is connected to a movable "tap" lead which can clip to any location on the heavy primary coil. By moving the tap lead, the primary coil inductance is varied, and the tank circuit frequency can be changed.

With one capacitor terminal connected to each end of the primary, I still have two free capacitor terminals. Across these terminals I place the gap, and the HV feed lines.

When HV 60 cycle current is fed to the capacitors they charge. As the voltage rises, tension builds in the air gap. When the tension is sufficient, the gap breaks down and the capacitors are discharged rapidly. This spark gap acts as a high voltage switch. When the gap is open, the capacitors charge. When the gap fires, the caps are discharged in a pulse. Because of the voltage and currents involved, the gaps on larger coils employ a rotary break, almost exactly like a large car distributor at high speed.

This pulse discharging produces a large current (over 1000a@20kv in my system) from a modest transformer output (.5 amp @ 20kv). The pulse "rings" from capacitor plate, through the coil, to the second capacitor plate; and back again.

The frequency of the "ring" (oscillation) depends on the size of the cap, and the inductance (# of turns) in the coil. Since my capacitance is fixed, the coil size (inductance) is varied by moving the tap to a different location. In this fashion the spark gap oscillator is tuned. The parameters of this particular system allows frequencies from ~200 - 57 KHZ.

Now the secondary coil (specs in previous post) has a natural frequency of 132.5 KHZ. I load the secondary coil with top capacitance, most commonly a toroid shaped conductive terminal. This lowers the natural frequency of the sec. coil. My best results were obtained using a 40" diam. X 4" thick toroid discharger, lowering the frequency of the coil from 132.5 kHz to 79 kHz.

The secondary coil with discharger is placed upright in the center of the primary coil. The secondary coil base wire is ground to a heavy, dedicated, RF ground. The air terminal is of course the other connection.

By tuning the frequency of the primary tank circuit to match the frequency of the secondary coil, energy is transferred from primary coil to secondary coil thorough mutual induction. This is much like a common transformer, but at these frequencies an iron core is wasteful.

… If all else fails… Put another megavolt through it.

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Msg#: 1984                     Date:10-16-93  21:54 
From: Richard Quick            
  To: All             
Subj: 10KVA Tesla Coil 

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In essence the primary coil is an inductive RF transmitter, and the grounded secondary coil is an inductive RF receiver.

The secondary coil receives the energy from the primary and become electrically excited. The coil develops a 1/4 standing wave of the system frequency, hence "1/4 wave" Tesla coil, or "1/4 wave helical resonator" are descriptive terms. What that means is that the potential at the base of the coil (ground) is "zero". The voltage rises up the coil until you reach maximum potential at the top. This is essential to producing good spark.

If you look at a sine wave of one complete oscillation you will see half of the wave above the "X" axis, and half of the wave below the "X" axis. The point where the sine wave crosses the "X" axis is ground potential or "zero" voltage.

On the "Y" axis you will find the peaks of the sine wave located at the 1/4 points of the wave length. These "Y" axis peaks are the locations of the maximum voltage. The "X" axis crossings ("zero" volts) are the locations of maximum current in the wave.

So to come back to lay terms, the base of the excited Tesla secondary is at ground potential, but there is a lot of RF current flow. For the coil to operate, this current must be removed, hence a heavy RF ground is required.

The top of the coil is the high voltage end, where the 1/4 wave voltage peak is located. Since the voltage is RF, and the discharge terminal is air insulated, the voltage simply breaks down the air. Large sparks and streamers and corona leave the discharger in a display unequalled by anything else in my experience.

The high voltage can be trapped in the system by adding discharger capacitance until the spark will not break out. Energy is constantly fed into the coil from the primary, and the only escape is through radiation or the ground wire. Radiation alone simply cannot remove the energy in the coil, so massive currents are forced into the ground. This forms the basis of Tesla's system for wireless power transmission.

Experiments confirming his ideas can be performed with small coils. I took a single 6" Tesla secondary, no primary or tank circuit, just a coil and a discharger; and walked over a quarter mile, to a nearby creek. I grounded the coil by placing 10' of aluminum flashing in the creek water. Back in my basement, an assistant fired a Tesla coil that operated at the same frequency as my "free" coil in the creek. The system being fired was loaded with discharger, so spark could not break out.

Down in the creek I was able to light bulbs from the top of the grounded coil, despite the 1/4 mile distance (and don't forget a creek bank and a rebar wall) between my location and the power supply. This coil was not receiving radiated signal, it was resonating on base fed ground current.

Coils can be forced to operate at frequencies other than the natural 1/4 wave by top loading "extra" coils or other resonators on the end of the system. Tesla used this more complex "Magnifier Coil" circuit in the Colorado Springs machine. In the Magnifier, the secondary coil is forced to resonate at 1/8th, 1/16th, 1/32nd, or any other harmonic of the system frequency. A transmission line is used to take CURRENT from the secondary to a RESONATOR located away from the primary/secondary driver system.

The resonator may be helical (coil), coaxial, or cavity. In this way the Tesla system may be used as an efficient driver for experiments in other areas of physics. I have wondered about the possible use of a tuned cavity resonate laser tube, or linear particle accelerator. Another guy told me about a Russian using coaxial resonators for fusion.

Tesla built a system for the worldwide transmission of electrical power by top loading the "extra" coil (a base fed 1/4 wave helical resonator) so spark would not break out. This forced the tremendous energy to ground. He tuned the system so that the ground current was also earth resonate. This was a double ended resonator system of very high efficiency. The earth acted as a cavity resonator on the base (for the ground current) the extra coil was a helical resonator a with radiating discharger in the air. He stated the system was to be used as a multiplexed wireless transmitter from both the ground and air terminals (he had tuning and harmonic coils in the ground path).

… If all else fails… Put another megavolt through it.

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Msg#: 2110                     Date:10-20-93  00:18 
From: Richard Quick                 
  To: All                        
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ OK, back on topic.

I just dug up a catalog for some more source material. This one is the Tesla Book Company, P.O. Box 121873, Chula Vista, CA. 91912. They have a 1-800-398-2056 information, catalog, and ordering service. They carry a book "VACUUM TUBE TESLA COILS", and I believe that this is the same book that I am going to be referring to. The Book I am looking at, VACUUM TUBE TESLA COILS, is written by James & Kenneth Corum. You may also contact Corum & Associates, Inc. at 8551 State Route 534, Windsor, OH. 44099. I have met the Corums, they are for real.

I see some other publications worthy of note in this catalog: TESLA COIL DESIGNER is a computer program written by my friend Walt Noon, I use this program to determine ball park frequencies and inductances in mathematical simulation before I wind any coil. This software is menu driven and Walt has been very helpful in working out the bugs and adding features with me. It works and saves hours of designing time.

I see an entry here for Dr. Nickola Tesla's Diary 1899-1900. This was the time Tesla spent in Colorado Springs working on his monster oscillator, but this does not sound like the preferred reference, THE COLORADO SPRINGS NOTES which includes most of the printable photographs of the lab and the machine. However, the original prints of this work (as I look at my copy) are from NOLIT, in Belgrad, Yugoslavia, and are now expensive. 21st Century Books has copies, P.O.Box 2001, 100 South Ridge St. #101, Breckenridge, CO. 80424-2001, tel. 303-453-9293, but they want $100.00 where I paid $45.00 a few years back. I will have to take better care of mine…

Both of these companies sell "new age science", "zero point energy" and "scalar wave" material; which in my opinion is garbage and not worth the paper the printing is on.

Now the Corum book which I will talk about briefly, is a piece of hard core electronics engineer stuff, but it is worth trying to muck through for those who don't believe coil driven RF equipment can have "practical" uses in physics and electronics. It contains most of the important facts on "A Technical Analysis of the Extra Coil as a Slow Wave Helical Resonator". This refers of course to the function of the "extra" coil in Tesla's Colorado Springs machine. But the book is much more. Tesla driven X-Ray machines, tapped coaxial helical resonators, particle accelerators, cavity resonators, etc.

The book has charts and diagrams even the most novice electronics buff would understand sandwiched between pages of calculus needed to design and construct the equipment. One page (XI-10) shows the development of conducting electrical resonators from Lord Kelvin through Tesla, to Schumann's verification of the earth as an electrical cavity resonator in 1952.

Books of this quality are rare, and make excellent reading for anybody interested in high energy electronics. It has an excellent bibliography.

In searching for material to lead to coil powered high energy devices I can say that this points to the right directions.

"The coaxial geometries do have the advantage of compactness and portability. And, this may be of significance to those interested in directed energy devices."

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Msg#: 2109                  Date:10-20-93  21:35 
From: Richard Quick          
  To: All                    
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ A couple of weeks ago someone posted me some "new to me" information about Russian RF resonator work that resulted in a machine capable of fusion. I asked for some additional information on this subject, and as of yet I have not heard back.

However, I have done some delving of my own and came up with some very interesting information about this guy (P.L. Kapitza). I stumbled across the name doing some related research (yes this thread is based in fact, and Tesla's work has practical apps)…

His name is Peter L. Kapitza, and he shared in a Nobel Prize in 1978 with Americans Arno Penzias and Robert W. Wilson for his work in magnetism and the behavior of matter at extremely low temperatures. His work on RF resonators was apparently done much earlier, as I find a reference to "High Powered Electronics" in a Russian periodical, Uspekhi Fizicheskikl Nauk, Vol 78 (November 2, 1962, pp. 181-265). In the same bibliography I find another "more unusual" reference by physicist Jerzy R. Konieczny "New Weapon 'X'" in a Polish periodical, Wojskowy Przeglad Lotniczy, (November 2, 1963, pp. 72-75) apparently referring to a particle beam device…

A little more research back to Kapitza, turned up Tesla's name in a quote!!! (See Margaret Cheney, TESLA, MAN OUT OF TIME, pp.284, Dorset Press, 1981, available from Barnes & Noble, 126 Fifth Ave, New York, NY 10011, tel 201-767-7079)

The quote is too long to reproduced here (it refers to high powered particle beams), but it clearly shows Kapitza was very much aware of Tesla's work in this country. Tesla was, by the way, the first to investigate "magnetism and the behavior of matter at extremely low temperatures" in the search of super- conductivity for his coils. Kapitza credits him.

Tesla lost a laboratory in New York, to fire, at 2:30 A.M., March 13, 1895. The fire is believed to have been caused as a result of liquid air leaking from his equipment. Tesla stated to the fire officials at the time that the air liquidation equipment was the only thing left running in his absence. He used the liquid air to cool his coils for experiments in high efficiency magnetism…

Now I'm not saying this means anything… but I keep finding these references dancing around the subject of particle beam weapons, fusion, high energy lasers, and power transmission without wires. These are modern references mind you, not Tesla's; but the deeper I dig, the more I find Tesla's name.

I am also finding out more information on involvement of "National Security" interests in these references. I mentioned about James & Kenneth Corum having a paper taken from them after a presentation by the FBI. In Cheney's book (pp. 310) we find this… "the U.S. government has deemed the material important to national security and has been at great pains to conceal it's existence." She is referring to all of Tesla's advanced (and of course unpublished) research and papers taken into U.S. custody at the time of his death.

Now I am sick to death of hearing about Tesla conspiracy, ad nauseam. But I ask this based on fact (check em yourself). If the work Tesla did in these areas does not yield workable devices, then why would there be a "national security" interest? Tesla laid the ground work for people like Kapitza, Konieczny, and our own SDI projects.

Again, I will state that it is not illegal to build coils or other resonators, lasers, particle accelerators, masers, rail guns, etc. Though I sometimes feel that the government wants everything but taxes made illegal.

I am still not able to locate any information in english on Kapitza's RF resonator fusion machine. So whoever sent me the post, please keep digging.

Now back to the topic…

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Msg#: 2133                          Date: 10-21-93  17:41 
From: Richard Quick              
  To: All                        
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ The Tesla Magnifier

What exactly is the Tesla Magnifier, and how does it differ from the standard 1/4 wave Tesla Coil? This question has been asked over and over in the past 93 years. I think I can give some insight into this for a better understanding of the system. A lot of the information I will present here (to the best of my knowl- edge, feel free to prove me wrong) appears in text form for the first time.

I have explained in some detail the set up and basic operation of my 10KVA 1/4 wave system. To get a mental picture of how the coils are physically positioned for firing in this 1/4 wave system, imagine a 12" phonograph record, with a Quaker Oats canister sitting upright on the center. The phonograph record represents the wide flat primary coil, and the oats canister represents the 1/4 wave secondary coil. The secondary coil would be topped with a toroid shaped discharger.

These coils are "loosely coupled", "coupling" in coil systems refers to the mutual inductance between primary and secondary. The coupling is kept loose because these coils are capable of such high energy transfers that the secondary is overdriven or "split" if placed in too close proximity to the primary. Splitting of the secondary is seen in coils that are over driven or "over coupled". The excess energy absorbed in the secondary coil causes a frequency split with the result that harmonic 1/4 wave voltage peaks appear in the secondary coil windings. These harmonic peaks show up as sparks that break out from the sides of the coil. If the coupling is not loosened, or input powers reduced, the coil will be destroyed in short order.

This is a serious limiting factor in 1/4 wave Tesla systems. "Critical" or perfect coupling limits the amount of energy that can be processed through the system. Large toroid dischargers assist in unloading the secondary, and allow for closer coupling, but this is like treating the symptom, not effecting a cure.

The problem with the 1/4 wave coil system is that all of the energy processed in the system remains trapped in the secondary until it is removed by spark. As spark lengths and input powers grow, so do coupling problems. Strain is also put on the tank circuit. Energy can flow in both directions in the 1/4 wave system, and secondary energies can unload not only in spark from the discharge terminal, but can also flow back into the primary tank circuit. This results in nightmarish problems "quenching" the arc at the main system spark gaps. In theory no more than 50% of the input energy can be converted into discharge off the secondary air terminal, as both primary and secondary energies equalize before a break can be effected at the main system spark gap. Once the break (open, non-firing spark gap) is made, the secondary energy is trapped, and must be radiated or discharged.

Tesla realized that critical coupling limited the efficiency of the system, and came up with a unique solution. He added an "extra" coil to the secondary. The extra coil is a normal 1/4 wave helical resonator, or Tesla secondary. The coil was placed away from any inductive effects of the primary/secondary "driver" coils, and was bottom fed by transmission line with the output of the driver secondary. Tesla was able to determine certain "harmonic" shifts in the system, but nobody else was able to figure out what was happening for years and years.

What is happening is this. In order for the "extra" coil to function properly it must be fed RF current that matches it's natural 1/4 wave frequency. In order to provide a working system, the output of the secondary driver coil in his three coil Mag- nifier must be shifted away from it's normal 1/4 wave output.

The normal 1/4 wave output (high voltage peak) of the Tesla secondary must be shifted to a lower harmonic in order for the extra coil to receive current. If you base fed an extra coil with 1/4 wave voltage peaks, all you would get would be sparks from the transmission line, and a fire at the base of an extra coil (I've done it). Experiments, and review of Tesla work show that the 1/8 wave harmonic is preferred. The extra coil will cause some shifting of the driver coil output, but the system operates best when THE DRIVER COIL IS WOUND WITH THE PROPER LENGTH OF WIRE TO FACILITATE 1/8th WAVE OUTPUT.

This boosts efficiency in several ways. First, the energy in 1/8th wave output is about 20% greater than the energy of a 1/4 wave peak. The 1/8th wave location on the sine represents 70% of the wave energy, as opposed to 50% of the energy at the 1/4 wave point; the 1/8 wave point being the product of both current and voltage at this location on the sine. While this may seem a little technical to the novice, a 20% gain is realized by shifting the output to the lower, 1/8th wave harmonic.

The second increase in efficiency is due to the fact that the secondary, or driver coil, is no longer responsible for the end processing of the system energy. The majority of the resonate rise, or VSWR, occurs in the uncoupled resonator located some distance away, and fed by transmission line. The secondary is no longer stressed by a high voltage point at the top of the coil, and the current produced in the secondary is removed rapidly by the transmission line to the end resonator (extra coil).

The third boost to efficiency is the ability to tighten the coupling between the primary and secondary driver set. The coils can be placed with much greater mutual inductance (tighter coupling). Energy can then be forced into the driver in much larger amounts without the problems of splitting and breakdown. The coils can be arranged more like two nested buckets, with one inside the other, as opposed to a phonograph record with an oats canister on top.

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Msg#: 142                           Date: 10-24-93  20:25 
From: David Tiefenbrunn                
  To: Richard Quick                      
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ On 10-20-93 Richard Quick wrote to David Tiefenbrunn…

RQ> RQ> The following instructions are for a pulse discharging RQ> RQ> capacitor with a .02 uf at 35 kvdc rating. Thanks for the rest of the info.

I was talking to another engineer that I know, and I mentioned your Tesla coil. He has a 150W T-coil. We got to talking about spark gaps. It seems there used to be a rather large industry for them, back before vacuume tubes (and even larger than 10KW). One type was basically a stack of convex metal disks, with heatsink fins on the outside. The disks were spaced rather close together (maybe .05"?) but there were MANY in the stack. This spreads the heat around. Maybe something like that with compressed air cooling is a solution. I can try to get more info if you want. He was also aware of *room* sized spark gaps in use back then.

Dave

_ * OFFLINE 1.54 * I love the smell of ozone in the morning. -!- Maximus 2.01wb ! Origin: Abbey Road BBS Higganum, Ct. USA (1:320/5967) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 139 Date: 10-26-93 11:57 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ >a two hour video tape in exchange for: One blank (high >quality) VHS tape, a postage pre-paid return mailer, $10.00 to >pay for my time and effort in seeing that you get a high >quality, two hour, recording of my work. Note this offer is >not made on my behalf to make any money, and I am not >resposible for anybody's safety should they decide to >replicate any of the experiments I perform. I will send a >glossy print for $1.00 and a SASE. RQ>Richard T. Quick II, 10028 Manchester Rd., Suite 253, >Glendale, Missouri, 63122, USA DH> Two comments: DH> 1) - What IS your monthly electrical bill I'd rather not go into electric bills, let's just say it's going to get worse… DH> 2) - The $10 is in the mail Monday I will be sure you get lots of Arcs & Sparks for your hard earned money. I will get the tape out the following mail day. It would help to know if you are more interested in seeing spark or techinque. DH> have been a wee fan of Tesla for a looong time - talking DH> with some people now about maybe building a BIG one out in DH> Seattle - have done a few small ones. Big coils are a challenge. But I really think (and experiments prove) that the Magnifier System is more efficient as you scale up. Large 1/4 wave Tesla coils are not nearly as efficient. Send me a post and let me know what you think of the video. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12

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Msg#: 172                           Date: 10-27-93  13:29 
From: Richard Quick                            
  To: David Tiefenbrunn                        
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DT> Thanks for the rest of the info.

No problem, I hope you find it useful, I sure have. You don't see plans for components like that everywhere.

DT> I was talking to another engineer that I know, DT> and I mentioned your Tesla coil. He has a 150W DT> T-coil. We got to talking about spark gaps. DT> It seems there used to be a rather large industry DT> for them, back before vacuum tubes (and even larger DT> than 10KW). One type was basically a stack of convex DT> metal disks, with heatsink fins on the outside. The DT> disks were spaced rather close together (maybe .05"?) DT> but there were MANY in the stack. This spreads the heat DT> around. Maybe something like that with compressed air DT> cooling is a solution. I can try to get more info DT> if you want. He was also aware of *room* sized DT> spark gaps in use back then.

I am always interested in more information. I live for the stuff. As to the gaps you are describing, they are called "quench" gaps. The metal discs are separated by gaskets of mica. The mica gasket determines the gap distance between plates. The gasket prevents air exchange, so as the gap breaks in, the O2 is consumed and they run with in a nitrogen atmosphere.

These plates were machined to very close tolerances, and the actual electrode surface was kept fairly small. The large plate was used for a heat sink. The best gaps of this type were German made by Telefunken.

The advantage of the quench gap is they produce a continuous wave (undamped) oscillation in the tank circuit. They were employed in the first long range Tesla transmitters. Most of the major ship lines (with the exception of White Star I believe) used Tesla transmitters with Telefunken quench gaps. Telefunken had contracts with the shipping lines for gap service, and after so many hours of operation the gap would be removed by a certified Telefunken technician, cleaned and serviced. Per contract nobody else was allowed to break the seals. Telefunken had facilities in every major port.

Tesla used disruptive breaks in his demonstrations, but clearly documented that continuous waves from quenched or CW gap systems were used for transmission of electricty (both for power transmission and radio). Now this is where is starts to get interesting. 1/4 wave Tesla systems produce much less spark with a quench gap, but they will light low pressure gas bulbs many yards away, so they definately radiate much better. But the Tesla Magnifier with a quench gap produces excellent spark, AND radiates over long distances, especially if sparks are prevented by loading it up with discharger.

The problem with high powered systems running quench gaps is as you say, the gaps get huge, and you would almost need a cooling tower to remove the heat. This heat represents high loss from the tank circuit. Tesla solved this problem too, but the solution is not well known. He began running multiple phases directly into his oscillators, up to 6 phases in the experimental Colorado Springs, and 4 phases in the commercial Wardenclyff plant on Long Island. By using a quench gap system in series with a rotary break running at very high speeds (40,000 BPS and possibly even higher) he was able to obtain CW output from a disruptive (read rotary) gap system. This way he was able to reduce loss, keep the size under control, and still get CW output; at the same time he was able to really increase the power processed by the system. This is the type of system required for more advanced work with coil powered directed energy devices.

… And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 200 Date: 10-30-93 09:52 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>THIS POST MAY BE A REPEAT. MY SYSOP INFORMED MY 10/29/93 THAT RQ>HE TURNED OFF ALL CONFERENCES FOR OUTGOING MAIL 10 DAYS AGO BY RQ>MISTAKE. WHAT A MESS! The Tesla Magnifier What exactly is the Tesla Magnifier, and how does it differ from the standard 1/4 wave Tesla Coil? This question has been asked over and over in the past 93 years. I think I can give some insight into this for a better understanding of the system. A lot of the information I will present here (to the best of my knowl- edge, feel free to prove me wrong) appears in text form for the first time. I have explained in some detail the set up and basic operation of my 10KVA 1/4 wave system. To get a mental picture of how the coils are physically positioned for firing in this 1/4 wave system, imagine a 12" phonograph record, with a Quaker Oats canister sitting upright on the center. The phonograph record represents the wide flat primary coil, and the oats canister represents the 1/4 wave secondary coil. The secondary coil would be topped with a toroid shaped discharger. These coils are "loosely coupled", "coupling" in coil systems refers to the mutual inductance between primary and secondary. The coupling is kept loose because these coils are capable of such high energy transfers that the secondary is overdriven or "split" if placed in too close proximity to the primary. Splitting of the secondary is seen in coils that are over driven or "over coupled". The excess energy absorbed in the secondary coil causes a frequency split with the result that harmonic 1/4 wave voltage peaks appear in the secondary coil windings. These harmonic peaks show up as sparks that break out from the sides of the coil. If the coupling is not loosened, or input powers reduced, the coil will be destroyed in short order. This is a serious limiting factor in 1/4 wave Tesla systems. "Critical" or perfect coupling limits the amount of energy that can be processed through the system. Large toroid dischargers assist in unloading the secondary, and allow for closer coupling, but this is like treating the symptom, not effecting a cure. The problem with the 1/4 wave coil system is that all of the energy processed in the system remains trapped in the secondary until it is removed by spark. As spark lengths and input powers grow, so do coupling problems. Strain is also put on the tank circuit. Energy can flow in both directions in the 1/4 wave system, and secondary energies can unload not only in spark from the discharge terminal, but can also flow back into the primary tank circuit. This results in nightmarish problems "quenching" the arc at the main system spark gaps. In theory no more than 50% of the input energy can be converted into discharge off the secondary air terminal, as both primary and secondary energies equalize before a break can be effected at the main system spark gap. Once the break (open, non-firing spark gap) is made, the secondary energy is trapped, and must be radiated or discharged. Tesla realized that critical coupling limited the efficiency of the system, and came up with a unique solution. He added an "extra" coil to the secondary. The extra coil is a normal 1/4 wave helical resonator, or Tesla secondary. The coil was placed away from any inductive effects of the primary/secondary "driver" coils, and was bottom fed by transmission line with the output of the driver secondary. Tesla was able to determine certain "harmonic" shifts in the system, but nobody else was able to figure out what was happening for years and years. What is happening is this. In order for the "extra" coil to function properly it must be fed RF current that matches it's natural 1/4 wave frequency. In order to provide a working system, the output of the secondary driver coil in his three coil Mag- nifier must be shifted away from it's normal 1/4 wave output. The normal 1/4 wave output (high voltage peak) of the Tesla secondary must be shifted to a lower harmonic in order for the extra coil to receive current. If you base fed an extra coil with 1/4 wave voltage peaks, all you would get would be sparks from the transmission line, and a fire at the base of an extra coil (I've done it). Experiments, and review of Tesla work show that the 1/8 wave harmonic is preferred. The extra coil will cause some shifting of the driver coil output, but the system operates best when THE DRIVER COIL IS WOUND WITH THE PROPER LENGTH OF WIRE TO FACILITATE 1/8th WAVE OUTPUT. This boosts efficiency in several ways. First, the energy in 1/8th wave output is about 20% greater than the energy of a 1/4 wave peak. The 1/8th wave location on the sine represents 70% of the wave energy, as opposed to 50% of the energy at the 1/4 wave point; the 1/8 wave point being the product of both current and voltage at this location on the sine. While this may seem a little technical to the novice, a 20% gain is realized by shifting the output to the lower, 1/8th wave harmonic. The second increase in efficiency is due to the fact that the secondary, or driver coil, is no longer responsible for the end processing of the system energy. The majority of the resonate rise, or VSWR, occurs in the uncoupled resonator located some distance away, and fed by transmission line. The secondary is no longer stressed by a high voltage point at the top of the coil, and the current produced in the secondary is removed rapidly by the transmission line to the end resonator (extra coil). The third boost to efficiency is the ability to tighten the coupling between the primary and secondary driver set. The coils can be placed with much greater mutual inductance (tighter coupling). Energy can then be forced into the driver in much larger amounts without the problems of splitting and breakdown. The coils can be arranged more like two nested buckets, with one inside the other, as opposed to a phonograph record with an oats canister on top. … If all else fails… Put another megavolt through it. SLUG-BBS_The Most Unreliable Feed in St. Louis! _ Blue Wave/QWK v2.12

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Msg#: 201                           Date: 10-30-93  09:55 
From: Richard Quick                             
  To: Guy Daughterty                            
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>THIS POST MAY BE A REPEAT. MY SYSOP INFORMED ME 10/29/93 THAT RQ>HE TURNED OFF ALL CONFERENCES FOR OUTGOING MAIL 10 DAYS AGO BY RQ>MISTAKE. WHAT A MESS!

GD> Well, yeah, Richard. We all think you're wacky, and keep GD> looking toward your direction on the planet waiting to see GD> the kaboom.

GD> So, once the atmosphere DOES light, how do we turn it off GD> again? -!-

On your last question: Turn off the switch. I use multiple interlocks in case one or two fuse closed. Had it happen on the arc welder current limiter once. When I opened the cabinet to repair the switch, I noticed the variable shunt was also stuck and there were signs of arcing. But it is an arc welder…

First remark: Keep looking. Probably won't be a kaboom though, more like a bazzzap. Obviously even you see the potential.

But if everybody thinks I'm wacky, should I stop posting? I don't want to waste people's time. I just thought you all were interested.

… If all else fails… Put another megavolt through it.

_ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 203 Date: 10-30-93 10:02 From: Richard Quick To: Guy Daugherty Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>THIS POST MAY BE A REPEAT. MY SYSOP INFORMED ME 10/29/93 RQ>THAT HE TURNED OFF ALL OUTGOING MAIL FROM OUR BOARD TO THE NET RQ>ABOUT 10 DAYS AGO BY MISTAKE. WHAT A MESS! GD> Well I have a Jacob's ladder on an old theatre marquis neon GD> transformer. Really makes the kitty stop and pay attention. GD> Worries people who see it, too. My inner Beavis loves it. Yeah, I have some videos of the pole pig settin on the garage floor with 3/8" copper pipe rails. Pulls arcs clear to the rafters. Running the tape in slo-mo shows plasmoids forming at power levels over 5KVA. I have also messed with doping the rails with salts which modify the colors. You can get some pretty good Halloween effects with a couple of old neons and some strontium or lithium salts. By the way Guy, what grade are you in? … And if all else fails… Put another megavolt INTO SYSOP! _ Blue Wave/QWK v2.12

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Msg#: 210                           Date: 10-30-93  16:13 
From: Richard Quick                             
  To: Dave Halliday                             
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Dave,

I got your package in the mail today, and your tape went back out. It is after the pickup time on Saturday, but you should have the tape by midweek.

Let me know when you get it, and what you think. I am sorry I had to cut a lot of material out, but two hours just doesn't seem to be enough time to give you the tour, show you some techniques, and show all of the systems. I cut back on a lot of smaller test and prototype stuff to let you focus on the big coil.

If your interested in anything else, just let me know.

… And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 419 Date: 11-01-93 10:21 From: Guy Daugherty To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>But if everybody thinks I'm wacky, should I stop posting? I don't RQ>want to waste people's time. I just thought you all were RQ>interested. I'd guess that the ones of us who are doing similar research are completely engrossed with your findings and research- I think it's interesting, though I fail to see the utility of what the devil it is you're up to, as opposed to my productive reduction of lifespan, i.e., posting smartass remarks in a few conferences and running up the phone bill for dozens of sysops across the globe. I'm curious what your end goal is, if you believe that even if you can prove Tesla's principles and concepts to have the validity his proponents trumpet, how could your break into the lockup current utility companies have over the conversion and distribution of electrical energy. I have similar feelings about the use of dinosaur ooze for internal-combustion engine fuel –hydrogen would solve the pollution, supply limitation and toxicity problems– but I have no fantasy of it coming to pass in my lifetime. I say keep posting. We're interested. Plus, it narrows down the amount of territory we'll have to look for you in when something goes horriblly awry. -!- SLMR 2.1a Everybody's a dreamer, everybody's a star…. -!- GEcho 1.00 ! Origin: The Silhouetter bbs (209)472-0843 USR DS 16.8K (1:208/216) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 338 Date: 11-01-93 16:43 From: Robert Taylor To: Richard Quick Subj: 10KVA TESLA COIL ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Wanted to pass along some reference material that may be of interest. In addition to the _Tesla, Man Out of Time_ book, Barnes & Noble also has _The Inventions, Researches, and Writings of Nikola Tesla_ (edited by Thomas Martin–ISBN 0-88029-812-X)–I picked this one up form them for about $15 w/in the last 6-9 months–think they still show it in their catalog. The book is made up of transcripts of lectures & demonstrations given by Tesla, & several chapters are devoted to the coil & what he saw as its practical applications. Included are alot of technical details of his construction methods, as well as schematics. Unfortunately, there is nothing included as to the math that he used in design. While looking at this thread, I noticed that someone made mention as to a variety of spark gap designs. Some of this is covered–including magnetic & compressed air quenching. I did some fooling around with these designs a few years ago, but never got it to your level of development. Did not know the details of the oil-immersion cap at the time so I built a humongous Lleyden Jar cap for the tank circuit (after having blown up a ceramic high freq transmitter cap–not a pretty sight). However, did discover that a good power supply is a plain ol' 15 KV neon sign transformer (found some used ones at local sign shops). My biggest problem was working out the inductance–never could get the primary & secondary to sync properly–but it made one heckuva broad-band spark gap transmitter. Still interested in Tesla & his work. Quite a mind there. -!- Maximus/2 2.00 ! Origin: BLUFF CITY BBS (1:123/70) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 409 Date: 11-03-93 13:43 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Dave, RQ>I got your package in the mail today, and your tape went back >out. It is after the pickup time on Saturday, but you should have >the tape by midweek. RQ>Let me know when you get it, and what you think. I am sorry I had >to cut a lot of material out, but two hours just doesn't seem to >be enough time to give you the tour, show you some techniques, >and show all of the systems. I cut back on a lot of smaller test >and prototype stuff to let you focus on the big coil. GREAT! I will look forward to viewing it! Also, emphasis on the big coil is perfect. TTYL - Dave ë:-) b QMPro 1.51 b Tagline for mind readers: -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2529 Date:11-03-93 18:32 From: Randy Mcvittie To: All Subj: diode detectors ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RM> I am wondering if anyone else has tried using run of the mill silicon RM> diodes for measuring radiation. I have tried some diodes that I had RM> and I got a decent sized signal off of them and that got me to RM> wondering why the "Detector Diodes" cost so much, part of it is RM> gouging but for the most part electronics are VERY CHEAP to produce RM> once you get the process worked out. RM> RM> "Detector diodes" are like $500, the diode I used was about $0.05! RM> RM> For anyone wanting to try it out I used a plain 1N4007 and put my DVM RM> on it and then put the diode in a radiation field. RM> RM> 60KV 8.9 mVdc RM> 80KV 27 - 29 mVdc RM> 100KV 64 - 70 mVdc RM> RM> in a Cobalt 60 beam about 65mVdc RM> RM> On a Therac 20 High Energy Linear Accelerator RM> RM> 6MeV 348 - 239 mV (peak of pulses) RM> 9MeV 341 - 239 mV RM> 13MeV 403 - 350 mV RM> 17MeV 402 - 372 mV RM> X18MV 58 - 54 mV RM> RM> RM> I haven't done a lot of work on this yet, it just kind of hit me one RM> day that this could be worth a try. RM> RM> I haven't gone to the library yet to do a search but I'd appreciate RM> any info on this topic. RM> RM> RM> Cheers RM> RM> Randy…. RM> RM> RM> … OFFLINE 1.42 * We don't need no steenking tag lines… RM> -!- DlgQWK v0.71a/DLGMail RM> ! Origin: The Forge - 12 Lines, 2.3 Gig, 2xDHST, CD ROM (1:249/116) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 352 Date: 11-03-93 20:42 From: Richard Quick To: Robert Taylor Subj: 10KVA TESLA COIL ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RT> Wanted to pass along some reference material that may be of RT> interest. In addition to the _Tesla, Man Out of Time_ book, RT> Barnes & Noble also has _The Inventions, Researches, and RT> Writings of Nikola Tesla_ (edited by Thomas Martin–ISBN RT> 0-88029-812-X)–I picked this one up from them for about $15 RT> w/in the last 6-9 months–think they still show it in RT> their catalog. The book is made up of transcripts of RT> lectures & demonstrations given by Tesla, & several chapters RT> are devoted to the coil & what he saw as its practical RT> applications. Included are alot of technical details of RT> his construction methods, as well as schematics. RT> Unfortunately, there is nothing included as to the math that RT> he used in design. Math? Tesla did not use math. Seriously. Oh, he used some equations to give ballpark figures. But the numbers he was working with were for the most part taken from machines he had already constructed and were operating. Most of the math was not figured out until years and years later. The mathmatical treatise on extra coil work was not drived until the 1980's, Sloans work on resonators (mathmatical treatise) was not published until the 1930's. Tesla invented and built, he left the math for others to clean up later. RT> While looking at this thread, I noticed that someone made RT> mention as to a variety of spark gap designs. Some of this RT> is covered–including magnetic & compressed air quenching. The book is OK, but read it for generalities and direction only, outside of the schematics (which are his more primitve circuits) it should not be followed closely. We are in the age of plastics, and Tesla was in the age of wood, and rubber (carbon rich and a poor RF insulator). Some of the experiments are interesting, but I have performed many better ones that do not require $300.00 (modern prices) custom made tubes. RT> I did some fooling around with these designs a few years RT> ago, but never got it to your level of development. Did not RT> know the details of the oil-immersion cap at the time so I RT> built a humongous Lleyden Jar cap for the tank circuit RT> (after having blown up a ceramic high freq transmitter RT> cap–not a pretty sight). Good capacitance is a must! I too have built many, many, homemade capacitors and leyden jars. Blew every one! Your not coiling unless your blowing capacitors! Then when you get things worked out to where the capacitors stop blowing, you start blowing transformers. By this time though your usually running well over a killowatt and are getting (or have seen) some decent spark. Then you start working with power controllers, and HEAVY RF choking, next thing you know your in the big leagues. The best capacitors for beginners are salt water types. Bottles are filled with salt water, and placed in a salt water filled pan. The pan is lined with alum. foil, and a long bolt or some other conductor is placed in the bottle. The salt water in the pan is one plate, the salt water in the bottle is another plate, and the glass bottle is the dielectric. Oil can be poured over the water to reduce corona loss. Tesla used salt water caps on the Colorado Springs machine, and I have a friend running 5-8 KVA with plastic bucket salt water caps. RT> However, did discover that a good power supply is a plain RT> ol' 15 KV neon sign transformer (found some used ones at RT> local sign shops). I recommend beginners start with 9000 volt neons, then move up to 12,000 volt units before jumping into the 15s. The 15KV neons put too much stress on the capacitors (unless you are using glass leyden jars, or salt water caps with thick bottles). RT> My biggest problem was working out the inductance–never RT> could get the primary & secondary to sync properly–but it RT> made one heckuva broad-band spark gap transmitter. You just needed to learn the ins and outs of tuning. It takes a little practice. A lot of balancing is required to get optimum performance. Coupling, spark gap quenching, terminal capacitance, as well as the primary/secondary inductance all come into play. Sounds like you made a good start, to bad you did not take it any further. Thinking about picking it up again? With modern materials, a little time and effort, and modern designs, you would be surprised what you can achieve with coils. RT> Still interested in Tesla & his work. Quite a mind there. Me too, and I agree. Tesla was a man very far ahead of his time and technology. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12

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Msg#: 430             Rec'd         Date: 11-03-93  22:00 
From: Bob Stephenson                             
  To: Richard Quick                              
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ > GD> Well I have a Jacob's ladder on an old theatre marquis neon > GD> transformer. Really makes the kitty stop and pay attention. > GD> Worries people who see it, too. My inner Beavis loves it.

                                       ^^^^^^^^^^^^^^^ 

Oh man, I love it….Thank you!

Bob

-!- GEcho 1.00 ! Origin: Rock In A Hard Place - Teaneck, NJ (1:2604/109)

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Msg#: 482                           Date: 11-04-93  05:00 
From: George Powell                              
  To: Robert Taylor                              
Subj: Re: 10KVA TESLA COIL 

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using neon xformers..

Do you have any probs with the xformers heating up after a while? Using one as a jacobs ladder tends to get it quite hot after a time. Although after all the years of use/abuse, it's still ticking away and works fine. Is high temp a normal thing for these neon units? The temp is uncomfortable to touch..

Gp -!- Fruity Dog 6.0 ! Origin: Fruity Dog Support (1:2460/21)

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Msg#: 396                           Date: 11-04-93  19:17 
From: Richard Quick                             
  To: Robert Taylor                             
Subj: 10KVA Tesla Coil 

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I have read the book you mentioned in the post received here yesterday. I bought it from Barnes & Nobel last month and have read it cover to cover twice.

The books I mentioned earlier, (example _NICKOLA TESLA ON HIS WORK WITH ALTERNATING CURRENTS AND THEIR APPLICATION TO WIRELESS TELEGRAPHY, TELEPHONY, AND TRANSMISSION OF POWER_ ISBN 0-9632652- 0-2, from 21st Century Books, P.O. Box 2001, Breckenridge, Colo. 80424) is a much more informative work.

Tesla did not go public with much after he saw the tide of his fortunes turning. He kept his more advanced work very close to his chest. Even his basic experimental circuits used in developing the Magnifier were not published until the 1970's, the math not worked out until late in the 1980's, and the systems actually re-tested (with the exception of Golka's primitive efforts) until the last two years! Right now work on the Magnifier is at the point where any serious hobbyist can make a mark.

The book above is a candid interview with Tesla's attorneys in 1916 (after Wardenclyff), he talks, submits photographs, sketches, and schematics; all of which is recorded by stenographer. All documents submitted by Tesla are reproduced.

This book really cuts to the core. We see that Tesla used red herrings, even from the start, to disguise the true nature of his work. An example is his submission of photos and patent wrappers of an alternator. The alternator was patented (#447,920 March 10, 1891) as the power supply in a "Method of Operating Arc Lamps". Yet Tesla goes on to produce schematics showing it as the signal generator for the first radio, AND shows how the circuit evolved in a matter of months into a powerful lumped tuned circuit transmitter.

He submits schematics of his experimental tank circuit used in the New York lab prior to leaving for Colorado Springs, complete with three phase synchronous gaps (never published or patented). We see photos taken from Wardenclyff powerplant showing huge four phase high frequency alternators, and text describing the operation and performance.

The Colorado Springs notes are another example of Tesla revelations. Tesla never intended those notes be published, and we see circuits in there that are meaningless, until you add perhaps a little note from the book mentioned top. We see the circuit that Tesla used to create ball lightning in the lab (Colorado Springs Notes pp 115,162), advancements made on the three phase gap (but not showing the gaps, just the improvement).

Then we add information gleaned from the Corums' book _VACUUM TUBE TESLA COILS_ (ISBN 0-924758-00-7) and we begin to see that his later claims of particle beam weapons, worldwide power transmission, robotics, etc. are not based on some "crackpot's fantasy" (as Guy Daugherty would have some believe).

He completed all of the basic research, had an operational worldwide transmitter (Wardenclyff, look at the powerplant photos) though nobody had receivers yet. He had operational remote control robots (ISBN 0-9632652-0-2, pp 157 {photo}, patent 613,809 11/8/1898!).

I guess what I am trying to say is that his lectures, published explanations, even to some extent his patents are misleading, and deliberately so. You have to dig into sources that Tesla did not intend to become public, then you have to build and test these systems, then you are on the road to his later secrets. But they all seem to reach back to his 1/4 wave coil systems and the lectures, for the roots. The problem is that the work he presented in the lectures is now obsolete, both from a design and engineering point of view. With exception of some of the experiments, skip on to the material I have documented. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 559 Date: 11-04-93 20:28 From: Mark Lawton @ 930/20 To: Richard Quick Subj: 10kva tesla coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>But if everybody thinks I'm wacky, should I stop posting? I don't RQ>want to waste people's time. I just thought you all were RQ>interested. No! Keep the Tesla info comming. I've been building coils for 25+ years. Your description of the magnifing coil is the best I've heard. Before you burn a hole in the Earth, let me know, I want to get a picture of it! <g> Mark Lawton 71740,2005 === * WinQwk 1.30 #279 * Bonehead Racing - Off-road ATV Champions -!- InterPCB 1.50 # Origin: Dallas Remote Imaging Group BBS 214-394-7438 (8:930/20) ! Origin: Gateway System to/from RBBS-NET (RBBS-PC 1:10/8) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 560 Date: 11-04-93 20:32 From: Mark Lawton @ 930/20 To: Richard Quick Subj: 10kva tesla coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> GD> Well I have a Jacob's ladder on an old theatre marquis neon RQ> GD> transformer. Really makes the kitty stop and pay attention. RQ> GD> Worries people who see it, too. My inner Beavis loves it. RQ> RQ>Yeah, I have some videos of the pole pig settin on the garage RQ>floor with 3/8" copper pipe rails. Pulls arcs clear to the Love it… Pole Pig = Jacob's Ladder PS Does anyone need some neon transformers? I've got 3 collecting dust. (2) 7500V & (1) 15000V ML === * WinQwk 1.30 #279 * Bonehead Racing - Off-road ATV Champions -!- InterPCB 1.50 # Origin: Dallas Remote Imaging Group BBS 214-394-7438 (8:930/20) ! Origin: Gateway System to/from RBBS-NET (RBBS-PC 1:10/8) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 437 Date: 11-04-93 22:11 From: David Tiefenbrunn To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ On 10-30-93 Richard Quick wrote to Guy Daughterty… RQ> RQ>THIS POST MAY BE A REPEAT. MY SYSOP INFORMED ME 10/29/93 THAT I didn't see it before… RQ> But if everybody thinks I'm wacky, should I stop posting? I don't RQ> want to waste people's time. I just thought you all were RQ> interested. I'm interested. On another un-usual experimental topic, have you ever seen / read about / or heard of a rail gun? Dave _ * OFFLINE 1.54 * Hey, is that thing SUPPOSED to smoke like that?

-!- Maximus 2.01wb ! Origin: Abbey Road BBS Higganum, Ct. USA (1:320/5967)

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Msg#: 398                           Date: 11-05-93  01:25 
From: Richard Quick                             
  To: David Tiefenbrunn                         
Subj: 10KVA Tesla Coil 

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Well Dave,

I talked with the architect again today. Things are firming up for a real lab.

The building so far is looking like this:

50' x 60' with 8' masonry walls and 8' sheet metal walls on top. This gives a total wall height of 16 feet, with a slope up to the center of the roof for a 20' peak.

The half masonry, half sheet metal wall was a compromise for security, cost, and you'll never guess what else… My testing shows an all metal walled building will induct, and large currents will cruise through the structure. So masonry for the first 8' feet seems a good compromise.

For electrical service I'm getting 480 volt 3 phase, 400 amps, and 110/220 single phase 200 amps.

The building will have 4" x 15' galvinized pipe driven into the ground before the slab is poured as an RF ground, and I plan to extend it later. Thought I would drop you a line and let you know, as I was pretty excited to see some drawings. -!- … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 05 Nov 93 02:22:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ If you are interested in making a high voltage, high current, power supply, I can tell you how to do it for free…. First call the local neon shop(s) and tell them that your working with Tesla coils. Ask them to hold all of their failed xfrmrs so you can pick them up. Make sure you talk to the boss or foreman, and tell them that you want dead units. I have never had a shop turn me down for free cores. They are happy to get rid of them. There are two types of failed neon xfrmrs: warranty units, and old junk. The local shop must return units that fail within the two year warranty period back to the distributor for credit. Old junk (older than two years) you can pick up for free right from the local shop, but I also scavenge from the distributor. Ask where the failed warranty units go. If you can locate the distributor who sells wholesale, and handles failed warranty units, you have found a gold mine of high voltage xfrmrs. The distributor removes the PLATE from the xfrmr for return to the manufacturer, and throws the unit away. The manufacturer credits the distributor for the plate, as the shipping is too expensive. The cores go to the dumpster. After locating your source of failed units, be selective. Try to bring home the high current units. Ratings commonly used are 9 kv, 12 kv, & 15 kv, with common current ratings of 30 & 60 ma. Once in awhile you will come across a 120 ma unit. I grab all of the high current units (60 ma+) I can get in these voltages. First test your units. Use wire with a 15 kv rating or better. This wire can be obtained where you pick up the transformers. If you ask they will usually cut you off a few feet for free. I prefer using the solid polyethylene core from RG-213 coax, as it will withstand the voltage with gobs of extra safety margin. Draw an arc from the HV bushing to the case, one at a time. About 50% of the "failed" units I pick up are just fine and need nothing other than a clean up. There is nothing wrong with them. Often shops get these units from signs they have dismantled, and they just toss them into the junk pile with the rest. The other 50% are bad. Either one, or both, of the HV windings have broken down. These units can frequently be repaired. Remove all hardware, and insulators if possible. Take a hammer and a chisel and remove the cases by splitting them down the corners. Break off any stubborn insulators, but try to preserve the lead wire. You are left with a block of tar. Set the unit outside when it is very cold, and let it freeze solid overnite. The next morning, short the high voltage lead wires with a clip lead, and connect 110 volts across the primary. Since the cores on these transformers are shunted, they may be shorted without harm or blowing fuses. Let the unit cook for 15-30 minutes. Disconnect your leads, and with the chisel and hammer, chip a groove around the block. You want to score a groove lengthwise that will allow the block to cleave in two. Then starting from one end of the block, chip until you hit the core, then do the same with the other end. Pry and chip the tar away from the core until the xfrmr is free. The core may then be disassembled, and the windings removed and examined. Kerosene and a stiff brush will clean up the windings and core of any remaining tar. The "cold-cook" method is fast, clean, and works very well. Since the tar is frozen it chips away cleanly. The "cooking" softens up the tar around the core allowing it to release. The only other ways I know to free the cores are long soaks in solvent such as kero or gas, (the nasty waste does make a good crack filler), or melting out the tar with external heat from a fire or oven. Most units fail when the high voltage breaks down the tar insul- ation. The resulting carbon track shorts the winding. Simply removing the tar brings them back to life. Other times the coils break down internally. In this case I discard the winding after disassembling the core, and replace it with a good winding from another unit of the same model with the same type failure. While the core is apart, you can beef up the current output by removing a few of the shunting plates between windings. Never take out more than 2 or 3 of these plates per side, as the additional power output will burn out the secondaries. Generally I get about 70-75 ma out of 60 ma units after I have finished. Rebuilt units need a little protection from the high voltage secondary outputs. The first thing I do is solder on a new lead wire to the high voltage windings. The HV secondaries are wound with very fine magnet wire, in the 30 ma units the wire is not much thicker than a coarse hair. Once a good solder connection is made, bed the connection and the first 1/2 inch or so of lead wire to the top of the HV winding with hot glue or clear epoxy. The lead wire need not be anything special, any thin insulated stranded wire may be used. Heavy wire increases the chances of a failed connection due to mechanical stress. When setting the unit up to fire you simply have to route it on insulators. The windings themselves are wedged against the core to prevent vibration. I have seen wood, bakelite, and plastic wedges used commercially. What I like to do is to soften up some 30 mil polyethylene plastic sheet in boiling water, and heat the core in a warm oven. I wrap dry softened plastic around the core and gently force the windings down on it. Once cooled, the windings have some insulation from the core, and they will not vibrate. The base wire from the HV windings must be grounded to the core. Use the original grounding point if possible, if not you may split the core apart slightly with a thin blade and insert the wire into the gap before you clamp the core back up. If required you may splice on a small piece of wire for added length. Neon sign transformers that have been rebuilt may be fired dry. The tar used to pot the cores for neon use does not really insulate well against the RF and kickback from the Tesla Tank. The units last longer when they are freed of the tar potting. The only other choice is to sink rebuilt units in mineral or xfrmr oil which is a very good RF insulator. I choose to fire them "dry"; it works, and there is no mess. Neons may be run in parallel to deliver the current required to fire medium sized coils, and I have run up to 4000 watts with banked neon power supplies. The general practice is to run these banks off of 240 volt feeds controlled through a variac. Neons with matched outputs are run in pairs in these banks. The primaries are paired up in series, and the secondaries are all paralleled to the HV buss. Phasing is important here, and each transformer must be checked as it is added to the bank to ensure it is in phase with the other units. If an xfrmr draws an arc from a lead wire brought to the HV buss, the primary or secondary connections must be reversed. Neons typically have an efficiency of about 50%, in that they draw twice as much power as they put out. This problem can be resolved with the use of power factor correction (pfc) capaci- tance across the line. The pfc capacitors used are the same as for alternating current motors. The voltage rating should be at least twice the line current used, and I like a 4x voltage margin for long life. The formula used to determine ballpark pfc is as follows: 9 10^ C = Corrected kVA —— 2 2 f e^ This should read C = Corrected kVA times (10 to the ninth power) over, (2 pi times f times e squared) C = required capacitance in microfarads f = frequency of applied voltage e = applied voltage Corrected kVA is determined by dividing the volt*amps (watts) output of the neon sign xfrmr by 1000 Using a pair of rebuilt 12 kv, 60 ma neons, with 2 shunting plates removed from the core next to each HV winding, and power factor correction capacitance, you can get a nice 1.5 KVA Tesla power supply with over 90% efficiency. Total cost: $5.00 for the pfc capacitors, and a few hours of time. I have unpotted dozens of neon transformers from many different manufacturers. I have tried to make this as informative as possible, and have checked it over for mistakes. If I have erred, or was not clear on something, please let me know. Use common sense, and don't expect the first attempt to work out. On my first attempt I managed to destroy a HV winding during the unpotting, as I did not know where the windings were located on the core. But once you see one core unpotted, with minor differences, you have seen them all. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12

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Msg#: 441                           Date: 11-06-93  19:22 
From: Richard Quick                             
  To: David Tiefenbrunn                         
Subj: 10KVA Tesla Coil 

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DT> I'm interested. On another un-usual experimental topic, DT> have you ever seen / read about / or heard of a rail gun?

Sure, two different types.

Steve Hanson runs a particle accelerator rail gun in his basement. It is small, but it cooks!

He has extensive vacuum equipment, and the basic setup looks like this:

Two copper rods form the rails. They are set up in parallel bar fashion with the bases mounted in an insulator block. At the base of the rods, near the insulator, he wraps a tungsten filament removed from a common light bulb. He places a glass cylinder, like an elongated bell jar, with a target mounted in the closed end, over the rails. The jar is sealed at the base and pumped down to a hard vacuum.

Two high current lead wires are connected to the rails. They are epoxied into the insulator base so as to be air tight. He takes a HVDC power supply and charges a massive capacitor bank. He throws the switch, and BANG! the tungsten is vaporized.

The plasma is highly conductive, and maintains a current flow between the rails. The high current produces electro-magnetic force which propels the plasma under high acceleration down the rails and into the target. A regular microscope shows the plasma impact damage on plate glass targets. It really sinks the tungsten into the material.

Steve publishes a journal in which he covers his work. You may write to him at: 35 Windsor Drive, Amherst, NH. 03031.

The other type of rail gun uses a monorail system. A "bullet" of conductive material is loaded onto a single nonconducting rail surrounded by heavy coils. The coils are energized by a timed capacitive discharge. A special rotary gap with varied spaced electrodes may be used, but recent work points to computers to control to pulses. Timing is most critical.

The heavy current flow through a coil induces a current in any conductive material, in this case the projectile. The circulating currents in the projectile produce a magnetic field, which repels it from the coil. As it passes the next coil down the rail, the second coil is pulsed and so on. Since the current and voltage from the capacitive discharge is high, the forces imparted to the projectile are great. I believe the speed of sound has been broken by projectiles from small "hobby" guns.

I have not had contact with a working monorail gun. I have seen several photos. Information Unlimited, P.O. Box 716, Amherst, NH. 03031, tel: 603-673-4730 (9-5) may have additional information on monorail guns of this type.

Then there is this guy in California with a multi-gigawatt Taser gun….

The commonality of these systems is capacitive discharge, and power supplies. You must have HV pulse discharging capacitors and a high current, high voltage, power supply to experiment in these areas.

… If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 4 Date: 07 Nov 93 02:03:00 From: Richard Quick To: Guy Daugherty Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ GD> I'm curious what your end goal is, if you believe that even GD> if you can prove Tesla's principles and concepts to have the GD> validity his proponents trumpet, how could your break into GD> the lockup current utility companies have over the GD> conversion and distribution of electrical energy. We may never see this one, even if commercial feasibility is proven. But you are taking a bit of a narrow view, that is all. My personal goal is not only to prove Tesla's principals and concepts (which I believe has already done as far as his patents are concerned), but also for the pure search of knowledge. Practical applications, something I think may be possible to achieve, would be perhaps a true "high efficiency" laser. If we have one, then someone will figure out how to employ it for profit, maybe in fusion. Me, I am looking to spend money with this, not make it. You must be misunderstanding the breakthrough that the Magnifier circuit represents. Just because Tesla saw one commercial application for the circuit in a transmitter does not mean that this is the only single use, or the only use Tesla saw. This is definately not the case. The circuit is a very, very, very efficient RF power supply. It can be set up to provide RF current, or voltage (or both) depending on the intended app- lication. As a power supply for large tuned resonate loads there is nothing equal. In effect the circuit is narrow band RF signal generator capable of enormous powers. It is relatively cheap and easy to build, and the design and components are easily modified. The Magnifier was not recognized as a high efficiency, narrow band signal generator until the mid 1980's; 90 years after Tesla had industrial scale operational units, and a full ten years after Tesla's Colorado Springs Notes went into print for the first time. The photos published at the time (early 1900s) only show, and the only thing people remember, are the sparks. Yet in the opening pages of the Notes, Tesla clearly stated his intended goals for the machine, he does not mention sparks. In an era with no o'scopes, multimeters, RF detectors, or stabilized RF generators (other than his); Tesla proceeded to design, construct, and test, a narrow band RF signal generator driving a tuned 1/4 wave resonate load to a voltage of 9.5 Megavolts with RMS currents of 1100 amps. Figure it out Guy, thats 10.45 Billion watts. He did this with an input power of 250 kVA, and so named the circuit "The Magnifier". The only way he could judge the performance of the system was to tune for spark occasionally. The reason the system was so large was because physical size was the only way to contain the energy in the system without break- down. He had to keep his charge density low or he lost energy. He did not have plastic film type pulse discharge capacitors, poly- ethylene core coax, PVC jacketed wire, or any of the dozens of other modern materials I use daily. When Tesla perfected the circuit, the only 1/4 wave resonator in existance was the resonate coil. We now have coaxial, tapped helix coaxial, and pure cavity geometries. Tesla never mentioned coherant radiation, and now we have lasers and masers. The Kapitza fusion experiment and the maser are examples of modern applications of resonate loads. Both are cavity type 1/4 wave resonators driven by signal generators. In my recent research I ran across an article, "Cavity-Coupling Investigation for the Phermex 50 MHz RF Accelerator", by E.W. Pogue and F.R. Buskirk, IEEE Trans. on Nuclear Science, Vol. NS- 32, No. 5, October, 1985, pp 2852-2853. The boys at Phermex seemed really excited to discover an increase of performace in the accelerator when run off parallel drivers. Yet Tesla shows the SAME IDENTICAL CIRCUIT, and at least three variations, with notes relative to the performance and character- istics of each in The Colorado Springs Notes in 1899! See Colorado Springs Notes, pp 153-156, mid August 1899. The circuit is precisely identical, the only differences being the frequency of operation and the geometries of the resonator. Tesla BTW was running powers an order of MAGNITUDE greater the the Phermex team. The magnifier is a very efficient signal generator, NOT a transmitter unless you CHOOSE to set it up as one. The entire purpose behind the magnifier circuit, it's only true function, is to drive resonators, not to transmit power. So lets forget the sparks for a moment, and lets forget global transmission of power. Why not hook the system to a tuned 1/4 wave resonator designed as a laser tube? A system 1/10th the power of Tesla's Colorado Springs oscillator would deliver a billion watts. With modern materials the size could be reduced greatly because we can insulate with plastics. In real dollars the cost is cheaper than Tesla's because we can tap the industrial surplus markets, transformers he paid thousands for then, I can buy surplus for a few hundred. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 633 Date: 11-07-93 12:15 From: Guy Daugherty To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>I talked with the architect again today. Things are firming up RQ>for a real lab. RQ>The building so far is looking like this: RQ>50' x 60' with 8' masonry walls and 8' sheet metal walls on top. RQ>This gives a total wall height of 16 feet, with a slope up to the RQ>center of the roof for a 20' peak. This is geting out of hand, Richard. -!- SLMR 2.1a You, you, and you panic. The rest of you, come with me. -!- GEcho 1.00 ! Origin: The Silhouetter bbs (209)472-0843 USR DS 16.8K (1:208/216) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 634 Date: 11-07-93 12:48 From: Guy Daugherty To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> GD> I'm curious what your end goal is, if you believe that even RQ> GD> if you can prove Tesla's principles and concepts to have the RQ> GD> validity his proponents trumpet, how could your break into RQ> GD> the lockup current utility companies have over the RQ> GD> conversion and distribution of electrical energy. RQ>We may never see this one, even if commercial feasibility is RQ>proven. But you are taking a bit of a narrow view, that is all. Narrow view? Me? That'll shock 'em. RQ>My personal goal is not only to prove Tesla's principals and RQ>concepts (which I believe has already done as far as his patents RQ>are concerned), but also for the pure search of knowledge. RQ>Practical applications, something I think may be possible to RQ>achieve, would be perhaps a true "high efficiency" laser. If we RQ>have one, then someone will figure out how to employ it for RQ>profit, maybe in fusion. Me, I am looking to spend money with RQ>this, not make it. Well, now you've stumbled onto MY area of expertise. Send me a signed check and I'll show you some pointers… -!- SLMR 2.1a The less you bet, the more you lose when you win. -!- GEcho 1.00 ! Origin: The Silhouetter bbs (209)472-0843 USR DS 16.8K (1:208/216) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 07 Nov 93 16:14:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> Hi Richard - again, thanks for the fantastic video! Loaned DH> it to my dad this morning - he used to teach physics ( still DH> writes textbooks ) and is a Tesla fan too… DH> Anyway, I was wondering how you went about getting your pole DH> pig - line xfrmr - and how much it set you back… I called DH> our local City Light and they cannot sell them because of DH> the EPA regulations. They actually ship them to some company DH> overseas for salvage… I will try some of the smaller PUD's DH> and see if they are not so "Politically Correct" <grin> Well you can try the utilities, I did, with no luck:-( Unless you are willing to climb the fence into their transfer yard and climb back out, in the dark, with a 200+ lb. pole pig under your arm, you will not get one there :-) I bought mine from: Larry J. Rebman The Transformer Bank, Inc. University Technology Center 1313 Fifth St. SE Minneapolis, MN 55415 Tel: (612) 379-3958, Fax: (612) 379-5962 The transformers they sell are brand new GE surplus, certified PCB free. GE manufactures at their plant in Hanover, North Carolina. Unsold units sit in the yard, and on GE's balance sheet, for 5 years and depreciate. Once GE has depreciated them to zero, The Transformer Bank buys them for 50 cents a pound. The Transformer Bank enters all of the plate information from these surplus pigs into their database in Minneapolis. They will fax you the plate specs on any surplus pig in the Hanover yard. Once you have chosen the xfrmr you want by comparing a few plate specs, call them for a price, then send them a certified check. The retail cost is a little over $1.00 a pound, so figure a 230 pound, 10 KVA xfrmr, will run about $250.00. The Transformer Bank has a shipping contract with Consolidated Freightways. The units are shipped directly from the Hanover yard. The contractual rate is about 50% the normal retail rate, and the Transformer Bank passes the entire savings on to the customer. Figure about $50.00 shipping per 250 pounds. My pole pig ran $303.00, including shipping, and was delivered to me ten days from the date I dropped the certified check in the mail to Minneapolis. It arrived still strapped on the original pallet, and it had no dings, dents or chips. The pallet was heavily weathered as one would expect, but once the pig was cleaned up, it looked (and is) brand new. The unit came with certification papers that match the serial number on the plate, showing it to be PCB free. Copies of the certification are on file with GE, so disposal or transfer of the pig will not be a problem. In shopping for a pig, you should be looking for a unit with two high voltage bushings, no taps, 120/240 primary, and a secondary voltage of 14,400 volts or higher. Remember! I am accustomed to running pigs backwards! You will always see me refer to inputs and outputs in reverse of utility pratcice when I talk about pigs. Thus my "primary" is the actual secondary, and v.v.. The kVA rating on pigs are of course for continous duty. They will run 24-7 at the plate rating and not warm appreciably. You may run them at twice the rated kVA output for 5 min or so without any problem. 10 kVA seems to be a nice size for high powered Tesla work. The 15 kVA pigs have a substantially larger core, and require more energy to energize. Since the cores on these are shell wound, you will not encounter appreciable core saturation. These units must be run with a heavy current limiter or they will pull the entire neighborhood into your experiment. You should be able to energize them without dimming the lights. Due the the heavy current limiting required, your input and output voltage will be lower than your line. My 10 kVA pig has a rated output of 23,890 volts, but with current limiting, the calulated output is closer to 20,000 volts. Both resitive and inductive current limiting may be used. The inductive delay (about 1 sec.) in the current limiter and variacs make control pretty jumpy, so it is best to use at least some resistive ballast to smooth things out, especially if you are not accustomed to these powers. The smoothest coils use all resistive ballast, but things get pretty hot. The best combination seems to be 6 or more paralleled oven elements placed in series with an inductor. I opted for pure inductance because I hate to waste energy as heat, but I feel the tug on my variacs through the control wheel, and Gary has seen some arcing in the variac brushes when the current limiter finally lets loose. When I add some resistive ballast these problems are eliminated. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 463 Date: 11-07-93 23:46 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ > CORRECTION! I posted a formula for power factor correction capacitance in magnetic shunted neon sign transformers the other day. As my word processor was formatting the pages for a DOS text save the formula apparently got messed up. The ASCII character "pi" was stripped, and formula was more or less "disassembled". The text below the formula in the original post reads correctly, and the formula should look like this: 9 10^ C = Corrected kVA —— 2 2 f e^ That is C = Corrected kVA * (10 to the ninth) over (2 pi * f * e squared) Where C = capacitance required in microfarads f = frequency of applied voltage e = the applied voltage Corrected kVA is the Volt*Amps (watts) output divided by 1000. I apologize for any inconvenience! … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 522 Date: 11-08-93 00:07 From: Richard Quick To: George Powell Subj: Re: 10KVA TESLA COIL ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ > using neon xformers.. GP> Do you have any probs with the xformers heating up after a GP> while? Using one as a jacobs ladder tends to get it quite GP> hot after a time. Although after all the years of use/abuse, GP> it's still ticking away and works fine. Is high temp a GP> normal thing for these neon units? The temp is uncomfortable GP> to touch.. No it shouldn't really bother them. Neon sign xfrmrs have a low power factor due to poor regulation. This condition is purposely built into the xfrmr so that the current output can be controlled. This limitation prevents burn-out of the secondary windings. Consequently, the secondary of a neon sign transformer can be short-circuited without harm. The poor regulation can be traced to the magnetic shunt. The shunt acts acts to draw the magnetic flux away from the secondary coil. Transformers of this type are often called "magnetic leakage xfrmrs". As the current in the magnetic leakage xfrmr increases, more and more of the magnetic lines are bypassed through the shunt. As a result, fewer magnetic lines reach the secondary windings. Consequently, as more current is drawn, less voltage is produced. Under load, the efficiency of these type xfrmrs is around 50%. Half of the energy is bypassed through the shunt, and is converted into heat. These units get hot as a result, but are normally rated for continous duty. Unless the tar starts bubbling out (indications of a problem in the primary coil) they should be just fine. I just posted instructions on how to increase the performance of these xfrmrs from 50% to around 90% by unpotting, removing a couple of shunt plates from each secondary winding, and using power correction capacitance on the input line. They not only put out more power, but the input current is reduced by nearly 50%, and they don't get nearly so hot… Yet they are still limited, and may be used for jacobs ladders. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ

Msg#: 570                           Date: 11-08-93  11:07 
From: Dave Halliday                            
  To: Richard Quick                            
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>I talked with the architect again today. Things are firming up

>for a real lab. 

RQ>The building so far is looking like this:

RQ>50' x 60' with 8' masonry walls and 8' sheet metal walls on top.

>This gives a total wall height of 16 feet, with a slope up to the 
>center of the roof for a 20' peak. 

WOW! Do you plan to do shows? You could charge admission.

Sounds fantastic!

b QMPro 1.51 b Avoid polysyllabification…

-!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546)

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ

Msg#: 599                           Date: 11-08-93  11:08 
From: Robert Taylor                           
  To: George Powell                           
Subj: Re: 10KVA TESLA COIL 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ Quoting George Powell to Robert Taylor ⇐-

> using neon xformers..

GP> Do you have any probs with the xformers heating up after a while?

To be honest–has been a while since I've had my xformers to play with. But as I remember, the Jacob's Ladder hook-up didn't cause any unusual overheat. You might check the size of your initiating gap at the bottom of the ladder. If it's too close–it will put extra strain on the xformer.

One thought–if your xformer is in a small case, the overheat may be natural. The ones that I used were fairly big monsters that weighed in at about 20 lbs.

If yours is in a case about 5" high by about 10" long–then yours may be prone to overheating. However, if you have any questions as to your coil's integrity try using a VOM or continuity tester on both the secondary & primary & the case to make sure that there are no obvious shorts. A serious overheat can really test your fire insurance.

You might also want to hook your VOM up on the primary side & monitor your current draw (should be some specs on the case as to 120 VAC draw). If you see way-out draws or if the draw starts up w/ time–then you may have a problem w/ the windings.

Hope this helps you out.

Robert

… ZZAPP! Another one bites the dust! _ Blue Wave/QWK v2.12 -!- Maximus/2 2.00 ! Origin: BLUFF CITY BBS (1:123/70) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2726 Date:11-10-93 12:15 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Dave Halliday to Richard Quick 'bout Tesla Video ⇐- RQ> sections of my preliminary Magnifier work, which I encourage RQ> others to follow up on. If you and your friends decide to RQ> take on DH> That was at the beginning - fascinating because I was DH> completely un-aware that the other coil was involved - I DH> just thought it was part of the background because I could DH> not see any arcs coming from it. DH> Very interesting that so much of the energy from it could be DH> so closely coupled to the second coil… This will be a fun DH> winter project!!! The "extra coil" is completely uncoupled from the driver system. Current from the driver is being fed into the base of the free standing "extra" coil by transmission line. While you are not able to see in the video… The transmission line glows with corona from the heavy current. DH> I was talking with one of the people and they agreed to DH> start on a smaller coil - I was thinking in the order of 4" DH> diameter and about 3' long. The aspect ratio (height to width ratio) is important. The planned coil has an aspect ratio of 9:1 (36" long, 4" diam.) this should be reduced to no more than 5:1 on a 4" diam. coil. 6" coils work best with 4:1 aspect ratio, anything larger 3:1. DH> The vacuum gap looked easy enough to build. This gap underwent about two weeks of prototyping not shown in the video, but once it was working, it worked great. It has trouble at power levels over 5 kVA. After an evening on the big coil at 8 to 10 kVA I had some pitting and melting of the electrode faces. This was reduced as I cut back on the number of electrodes, increased the size (both length and diam.) of the electrodes, and allowed for a larger gap between electrodes. DH> file about building a capacitor also looks pretty DH> straightforward. I guess the main deal there is just to be DH> patient and very careful. I have a vacuum pump so getting DH> all the air bubbles out of it should be pretty DH> straightforward. These homemade capacitors are high Q, reliable, and relatively easy to build. Pumping them down will really help. > please feel free to fire of any questions to me. As > you can tell, I have some little experience with all of these > systems, and may be able to help. DH> Questions???? Hoooo boy - stand back! <G*10E8> DH> You talk a bit about the kind of plastic to use for form for DH> the secondary coil. There is PVC and ABS available readily. DH> You mention that PVC is better but you also say not to use DH> Schedule 40 - both kinds of pipe are rated as being Schedule DH> 40… PVC is the worst plastic for use in secondary coils. It is "lossy" (high RF dissipation factor) and has a low dielectric strength. But it is commonly used because, as you mentioned, it is available. Coil forms, regardless of material, should be as thin as possible. Schedule 40 is thick, and is rated for pressure use. Try to locate the thinner "drain" pipe or "flume duct" PVC or other thin wall plastic. If PVC is used, it MUST be dry (baked is preferred) and well sealed with a low loss sealant like poly- urethane or two part epoxy. DH> How about plexiglass… Acrylic and plexiglas is pretty good. Dielectric strength could be better, but the RF dissipation factor is much lower than PVC. I have a couple of small acrylic secondaries and I have been pleased with them. Plexi in large diam. tubes gets expensive. DH> What determines a certain plastic being good? Should I look DH> up the dielectric constants and select for a high number? A combination of dielectric strength, and the RF dissipation factor. PVC fails this test, and requires drying and sealing to make it suitable. Teflon is the best; good dielectric strength, and the lowest RF dissipation factor; then comes polyethylene, polystyrene, and polypropylene, all of which are good. The same standards are also used to judge capacitor dielectrics and for general insulation in Tesla work, and the plastics rate in the same order. You asked about power supplies: The pole pig info is on it's way. See my two part post on obtaining neons for free, and rebuilding them for high output, high efficiency, Tesla power supplies. Remember Tesla power supplies must be protected with extensive RF choking, and safety gaps. This is especially important with neons, which are much more delicate than pole pigs or potential xfrmrs. I also use bypass capacitors. For bypass capacitance across the power supply HV terminals you WANT a dielectric with a high RF dissipation factor. Barium titanate capacitors with a DC rating are ideal for this use. Use a 4x voltage safety factor. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 588 Date: 11-10-93 12:26 From: Richard Quick To: Mark Lawton @ 930/20 Subj: 10kva tesla coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Mark Lawton @ 930/20 to Richard Quick ⇐- RQ>But if everybody thinks I'm wacky, should I stop posting? I RQ>don't want to waste people's time. I just thought you all RQ>were interested. ML@9> No! Keep the Tesla info comming. I've been building coils ML@9> for 25+ years. Your description of the magnifing coil is ML@9> the best I've heard. Thanks for the vote of confidence. As for my description of the Magnifier circuit; it is accurate because I have built, tested, and documented a couple of prototype systems. Now I need a little more room to scale up, and a place where a system can remain standing after I have set it up. Where I fire now, if I were to leave a system set up for 48 hours others would be inconvienced with my "hogging" the floor space. ML@9> Before you burn a hole in the Earth, let me know, I want ML@9> to get a picture of it! <g> If you write I will send you a glossy photo of a magnifier in operation. I have a really hot, time exposure, showing the glowing transmission line, and spots where the coil has struck the transmission line. Sprays of corona are comming out of perforations in the insulation. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ

Msg#: 589                           Date: 11-10-93  12:32 
From: Richard Quick                          
  To: Dave Halliday                          
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Dave Halliday to Richard Quick ⇐-

RQ>I talked with the architect again today. Things are firming RQ>up for a real lab.

RQ>The building so far is looking like this:

RQ>50' x 60' with 8' masonry walls and 8' sheet metal walls on RQ>top. This gives a total wall height of 16 feet, with a slope RQ>up to the center of the roof for a 20' peak.

DH> WOW! Do you plan to do shows? You could charge admission.

DH> Sounds fantastic!

The thought has crossed my mind. The primary use of the structure would be of course R&D of the Magnifier on a medium scale, but rest assured it will see other uses as well. With room for storage, permanent set-ups, etc. Shows would be a snap to do. Not many people have seen the old Million Volts Through The Body trick, and it is a thrill to do, as well as to see.

… And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 645 Date: 11-10-93 12:43 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> Hi Richard - again, thanks for the fantastic video! RQ> DH> Anyway, I was wondering how you went about getting your pole > DH> pig - line xfrmr - and how much it set you back… I called > DH> our local City Light and they cannot sell them because of > DH> the EPA regulations. They actually ship them to some company > DH> overseas for salvage… I will try some of the smaller PUD's > DH> and see if they are not so "Politically Correct" <grin> RQ>Well you can try the utilities, I did, with no luck:-( Unless you >are willing to climb the fence into their transfer yard and climb >back out, in the dark, with a 200+ lb. pole pig under your arm, >you will not get one there :-) I bought mine from: I have tried six of the local PUD's - all with the same result… Some of the people there seemed genuinely interested in helping but they had their hands tied with all of the red tape… I *do* know where Seattle City Light has their transfer yard (it's really close to our local warehouse store ( Costco ) but the place is too well looked after and I think it would be a little hard to build a Tesla Coil while in jail… :) RQ> Larry J. Rebman > The Transformer Bank, Inc. > University Technology Center > 1313 Fifth St. SE > Minneapolis, MN 55415 RQ> Tel: (612) 379-3958, Fax: (612) 379-5962 GREAT!!!!! >Once you have chosen the xfrmr you want by comparing a few plate >specs, call them for a price, then send them a certified check. >The retail cost is a little over $1.00 a pound, so figure a 230 >pound, 10 KVA xfrmr, will run about $250.00. RQ>The Transformer Bank has a shipping contract with Consolidated >customer. Figure about $50.00 shipping per 250 pounds. RQ>My pole pig ran $303.00, including shipping, and was delivered to >me ten days from the date I dropped the certified check in the RQ>The unit came with certification papers that match the serial >number on the plate, showing it to be PCB free. Copies of the This is exactly the info I have been looking for! I also got your postings on neon sign transformers yesterday - the idea of getting the reject units from a sign company is obvious - should have thought of that one… <WHACK!> ( sound of head hitting desk ) RQ>In shopping for a pig, you should be looking for a unit with two >high voltage bushings, no taps, 120/240 primary, and a secondary >voltage of 14,400 volts or higher. Remember! I am accustomed to Info saved! RQ>Since the cores on these are shell wound, you will not encounter >appreciable core saturation. These units must be run with a heavy >current limiter or they will pull the entire neighborhood into >your experiment. You should be able to energize them without I was wondering why you put the limiter on the circuit… Again, thanks for the info! We will be starting out with neon transformers, I had mentioned in an earlier post that the first one will be about 2 - 3' tall, probably a 4" form - looking forward to drawing some sparks as well as experimenting with the magnifier! TTYL - Dave ë:-) b QMPro 1.51 b W-E-H-T-H-U-R: Worst spell of weather in six months… -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2 Date: 10 Nov 93 21:02:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ ><Imported from Archives, 10/10/93 message to Dave Bearrow>< DB> How did you go about winding your coil? What are the specs? The first step in winding a coil is to select a coil form. The coil form should be a low loss material (we are talking RF losses) like polyethylene, polystyrene, or polypropylene: but the most common material is PVC plastic drain pipe (thinnest wall is best) which is high loss. I used a section of PVC thin wall flume duct. Ratios of coil height to width are important. Small coils work best with aspect ratios (height to width) around 5:1 - 4:1, larger coils (over 8" diam.) have aspect ratios around 3:1. Now we are talking about the actual winding length here, so allow an extra inch or so of coil form on each end. Determine the length required and cut the ends square. The form must be sanded smooth of surface imperfections, dried thoroughly, and if PVC is used, it must be sealed. A good sealer is polyurethane, another is two part epoxy paint. By sealing the surface of the PVC before you wind on wire you can negate the excessive losses in PVC plastic coil forms. If necessary the coil form may be sanded again after the sealer had dried. The coil should be wound with good quality magnet wire. I use double Formvar enamel coated magnet wire. Magnet wire gives you maximum inductance. A coil should have over 900 turns, but not too much over 1000 turns. There is a little leeway here. Select a gauge of wire which will allow the aspect ratio and number of turns to fall within this range. I dug that up as it pretty much explains things, and you may have missed the post. DH> What determines a certain plastics being good? As I omitted in the other message, the dielectric constant is not the factor to go by when choosing a coil form. It is really preferable to use a plastic with the lowest dielectric constant. The reason for this is you want the distributed capacity of the coil to be as low as possible. Capacitance in a coil stores energy, and we want the throughput to be as rapid as possible. The distributed capacitance in a coil retards the current peak that follows the VSWR (resonate rise). Coils have enough problems with distributed capacity from the length of wire, the closeness of turns, and the number of windings. No need to make things worse by choosing a plastic with a high dielectric constant. What is most important in choosing a coil form material is the dissipation factor. The dissipation factor of all commercial plastics has been calculated, and somewhere in this mess I have those figures. If my memory serves me correctly, the standard RF dissipation factors are based on a frequency of 1 Mhz, close enough to judge if the plastic is suitable for coil work. The next important factor to look at is the dielectric strength. This should take second place to dissipation factors if your goal is to build the most efficient coil possible. Proper con- struction, more than anything, prevents electrical breakdown. Even if the dissipation factor is very low (good efficiency) it is best to use the thinnest wall coil form possible, even if the wall thickness is not able to retain a circular cross section when mechanically stressed. Just treat the coil gently. As far as the electrical strength of a coil wound on a very thin walled plastic tube, it should not break down internally if the WIRE IS NEVER ALLOWED INSIDE THE COIL FORM. Do not drill holes or introduce the wire into the coil. A hole anywhere on the coil sidewall will cause a failure regardless of the dielectric strength of the coil form plastic. My coils are capped top and bottom with plexiglass plates that are approximately the same thickness as the coil form wall. I use two-part epoxy cement, and I seal them airtight. It is OK to drill one small hole in the bottom plexiglas plate to equalize air pressure, but I do not. The air terminal capacitance is connected by lead wire (I just use the magnet wire and avoid splicing) from the top of the coil. The lead wire is "air wound" up to the terminal, with the turns about the same diameter as the coil, or a little smaller. You will see me doing this in the video when I set up for a low power test in the garage. The terminal capacitance must have a diameter greater than the coil form, or spark will break out; either from the top of coil, or from the air wound turns connecting the coil to the terminal. The other construction secret not covered in the video is the ground connection. Once the coil is wound and sealed I take the base wire and pull it up out of the sealant until it is free all the way to the beginning of the first turn. I clip off the excess wire, leaving about a 2" tail. I lay the tail on a metal block, and using a small ballpeen hammer, flatten it out as best I can. A strip of copper sheet about 3/4" by 2" is then cut from stock and bent slightly to match the curvature of the coil form. Solder the flattened tail to the back of the copper strip. Position the strip on the coil form just below the bottom turn of wire, and scribe a rectangle through the sealant all the way to the coil form plastic. Remove the sealer from the scribed area, then score and clean the bared plastic. I then use epoxy to bed the copper strip. This forms a high current grounding plate without drilling. Ground wire or strap (preferred) can be held in firm connection to the plate with tape or a large rubber band. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 898 Date: 11-10-93 22:10 From: David Tiefenbrunn To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ On 11-05-93 Richard Quick wrote to David Tiefenbrunn… RQ> Well Dave, RQ> RQ> I talked with the architect again today. Things are firming up RQ> for a real lab. RQ> RQ> The building so far is looking like this: RQ> RQ> 50' x 60' with 8' masonry walls and 8' sheet metal walls on top. RQ> This gives a total wall height of 16 feet, with a slope up to the RQ> center of the roof for a 20' peak. I'm in a similar situation. We recently purchased a 2.75 acre lot, and are designing our new home and lab / shop. So far, I'm planning a 26x56 ranch with full basement 8-9ft clearance, and since I plan to use trusses for the floor joists, the basement will be free of support poles. We will also have a 3 bay garage (2 for cars, 1 for projects), with switchable heat. Eventually build a shed for the 45KW generator. RQ> The half masonry, half sheet metal wall was a compromise for RQ> security, cost, and you'll never guess what else… My testing RQ> shows an all metal walled building will induct, and large RQ> currents will cruise through the structure. So masonry for the RQ> first 8' feet seems a good compromise. Sounds good to me. I was flipping through a friend's book about some of Tesla's work, and saw some pictures of his labs. Apperently he had an opening in the roof with a long pole & ball sticking out. Must have been something to see at night. RQ> For electrical service I'm getting 480 volt 3 phase, 400 amps, RQ> and 110/220 single phase 200 amps. YIKES! when your'e done with the 10KVA, are you going for 100KVA? <g> Iv'e got a video tape & etc. ready to mail out, just have to get to the post office. I put a few minutes of the first run of the 45KW generator on it, since you were interested and the tape is going your way anyhow. Dave _ * OFFLINE 1.54 * I love the smell of ozone in the morning.

-!- Maximus 2.01wb ! Origin: =Abbey Road BBS= Higganum, Ct. (203)345-7635 (1:320/5967)

Ž Area: FIDOElectr ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ

Msg#: 910                           Date: 11-16-93  15:37 
From: Dave Halliday                        
  To: Richard Quick                        
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> -⇒ SEZ Dave Halliday to Richard Quick ⇐-

RQ> RQ> Larry J. Rebman

> >               The Transformer Bank, Inc. 

He was out hunting until today - haven't called yet but will, probably tomorrow - I have these pesky clients who actually want me to do something for them… :)

RQ> RQ>My pole pig ran $303.00, including shipping, and was

>   >delivered to me ten days from the date I dropped the 
>   >certified check in the mail. 

RQ>Your shipping rate may be higher since you are all the way cross

>country, and your delivery time will most likely take longer. 
>Still, where else are you going to go? 

So true - one of the ( few ) down sides of living out here. Looking on the bright side though, I could have settled in Nome or Honolulu…

Actually the interstate trucking is pretty reasonable - I-90 goes straight into town and that is one of the major East / West routes.

>educated me on the EPA requirements. Do not accept a pig, even a

>free one, if it does not have PCB certification papers. Some pigs 

RQ>It is not the PCBs that bother me. The problem occurs if youwant

>to sell or dispose of the unit. With current regulations, and 
>lack of certification, you have a legal hot potato that can cause 

Gotcha! That thought occurred to me too - getting one might be easy but the eventual disposal would be a nightmare…

RQ>Another type of xfrmr excellent for coil work is the potential

>type xfrmr. These are potted in plastic, not tar, and are not 
>shunted like neons. They carry the HV ratings required, and/or 
>can be placed in series (two 7500 volt units for a total of 
>15KV). Since the cores are NOT shell wound, they will saturate, 

RQ>These xfrmrs are used to step down a kilowatt or two for cooling

>fans, and for line voltage sensors in substations; so they are 
>not manufactured in the quantities that pigs are. They are much 

I will have to call on that one - I spoke to the person who handles surplus disposal for Seattle City Light and he seemed to be enthusiastic about helping but his hands were tied by EPA regs. They do have a mechanism for public sale of surplus items so it shouldn't be too hard.

RQ>Yeah, neons are not built very solid. The secondaries are

>el'cheapo, as the thinnest wire possible is used. The failure 
>rate is pretty high even in their rated service. Since the copper 
>content is low, they are not commonly recycled, and the cores 

I guess because they are built by the thousand and considered a field replaceable unit and not repairable… Just pass the "savings" on to the sign owner…

>pile up quickly. The higher the output current rating, the better

>they are built. Once the tar potting is removed, they last much 
>longer in Tesla use. Tar is a very poor RF insulator. To a Tesla 
>discharge, the tar looks more like an impedance! Pick up dead 

We will go that route - again, I got the neon xformer post so we will start there!

RQ>capacitors if you want more than a few hours of heavy duty

>service from a bank of neons. 

I located a good source for 600 volt AC caps in the 1 to 6 mFd range - I will use the formula ( corrected version ) that you posted when we get going. Also, will have to send photos - looking forward to this!

RQ>As far as RF choking is concerned, the HV filter board I designed

>and built in the video is the best I have ever used. I have not 
>had a single xfrmr failure since I built it. Bypass capacitors on 
>neon power supplies must be center tap grounded, so I switch 
>to using a different capacitor setup. As the secondaries on neons 
>are center tap ground, so must the bypass capacitors. I use two 
>stacks of caps; each stack has a connection to a HV bushing, and 
>to the system ground. 

Great! Like I said, I already have some large ferrite torroids, I'll use them and the spark gap and get some caps. Another person ( used to be my tech person 'till they went into business for themselves ) has built a few - he always complained about transformers blowing up - I'll have to pass this info on if he is still involved. ALso, he was building coils a *lot* longer than 1/4 wave - still got some respectable sparks though…

Anyway, got to go back and print some more xmass cards - graphic artist is having us do 500 of them as a trial run - nice design and we played with some good paper / ink combo. Got to do the insides now.

TTYL - Dave ë:-)

RQ>… And if all else fails… Put another megavolt through it

>___ Blue Wave/QWK v2.12 

RQ>— WM v3.01/93-0100

> ! Origin: St. Louis Users Group BBS (314) 878-7614  

(1:100/4.0) (1:100/4.0 -!- b QMPro 1.51 b Reality is a crutch for those who can't handle homebrew

-!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546)

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Msg#: 2729                  Date: 11-10-93  22:16 
From: Richard Quick          
  To: Dave Halliday          
Subj: 10KVA Tesla Coil 

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<Imported from Archives, 10/10/93 message to Dave Bearrow><

DB> How did you go about winding your coil? What are the specs?

The first step in winding a coil is to select a coil form. The coil form should be a low loss material (we are talking RF losses) like polyethylene, polystyrene, or polypropylene: but the most common material is PVC plastic drain pipe (thinnest wall is best) which is high loss. I used a section of PVC thin wall flume duct.

Ratios of coil height to width are important. Small coils work best with aspect ratios (height to width) around 5:1 - 4:1, larger coils (over 8" diam.) have aspect ratios around 3:1. Now we are talking about the actual winding length here, so allow an extra inch or so of coil form on each end. Determine the length required and cut the ends square.

The form must be sanded smooth of surface imperfections, dried thoroughly, and if PVC is used, it must be sealed. A good sealer is polyurethane, another is two part epoxy paint. By sealing the surface of the PVC before you wind on wire you can negate the excessive losses in PVC plastic coil forms. If necessary the coil form may be sanded again after the sealer had dried.

The coil should be wound with good quality magnet wire. I use double Formvar enamel coated magnet wire. Magnet wire gives you maximum inductance. A coil should have over 900 turns, but not too much over 1000 turns. There is a little leeway here. Select a gauge of wire which will allow the aspect ratio and number of turns to fall within this range.

I dug that up as it pretty much explains things, and you may have missed the post.

DH> What determines a certain plastics being good?

As I omitted in the other message, the dielectric constant is not the factor to go by when choosing a coil form. It is really preferable to use a plastic with the lowest dielectric constant. The reason for this is you want the distributed capacity of the coil to be as low as possible. Capacitance in a coil stores energy, and we want the throughput to be as rapid as possible. The distributed capacitance in a coil retards the current peak that follows the VSWR (resonate rise). Coils have enough problems with distributed capacity from the length of wire, the closeness of turns, and the number of windings. No need to make things worse by choosing a plastic with a high dielectric constant.

What is most important in choosing a coil form material is the dissipation factor. The dissipation factor of all commercial plastics has been calculated, and somewhere in this mess I have those figures. If my memory serves me correctly, the standard RF dissipation factors are based on a frequency of 1 Mhz, close enough to judge if the plastic is suitable for coil work.

The next important factor to look at is the dielectric strength. This should take second place to dissipation factors if your goal is to build the most efficient coil possible. Proper con- struction, more than anything, prevents electrical breakdown.

Even if the dissipation factor is very low (good efficiency) it is best to use the thinnest wall coil form possible. Turns of wire, coats of sealer, and hard plastic end caps will stiffen the coil some. Low density polyethylene forms (such as wastebaskets) give coils with very high "Q" factors (a measure of efficiency) but are difficult to work with, as this plastic is VERY flexible.

As far as the electrical strength of a coil wound on a very thin walled plastic tube, it should not break down internally if THE WIRE IS NEVER ALLOWED INSIDE THE COIL FORM. Do not drill holes or introduce the wire into the side of the coil. A hole anywhere on the coil sidewall will cause a failure regardless of the di- electric strength of the coil form plastic. My coils are capped top and bottom with plexiglass plates that are approximately the same thickness as the coil form wall. I use two-part epoxy cement and I seal them airtight. It is OK to drill one small hole in the bottom plexiglas plate to equalize air pressure, but I do not.

The air terminal capacitance is connected by lead wire (I just use the magnet wire and avoid splicing) from the top of the coil. The lead wire is "air wound" up to the terminal, with the turns about the same diameter as the coil, or a little smaller. You will see me doing this in the video when I set up for a low power test in the garage.

The terminal capacitance must have a diameter greater than the coil form, or spark will break out; either from the top of coil, or from the air wound turns connecting the coil to the terminal.

The other construction secret not covered in the video is the ground connection. Once the coil is wound and sealed I take the base wire and pull it up out of the sealant until it is free all the way to the beginning of the first turn. I clip off the excess wire, leaving about a 2" tail. I lay the tail on a metal block, and using a small ballpeen hammer, flatten it out as best I can. A strip of copper sheet about 3/4" by 2" is then cut from stock and bent slightly to match the curvature of the coil form. Solder the flattened tail to the back of the copper strip. Position the strip on the coil form just below the bottom turn of wire, and scribe a rectangle through the sealant all the way to the coil form plastic. Remove the sealer from the scribed area, then score and clean the bared plastic. I then use epoxy to bed the copper strip. This forms a high current grounding plate without drilling. Ground wire or strap (preferred) can be held in firm connection to the plate with tape or a large rubber band.

… And if all else fails… Put another megavolt through it

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Msg#: 2729                          Date: 11-10-93  22:16 
From: Richard Quick 
  To: Dave Halliday 
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ

DH> What determines a certain plastics being good?

(for winding coils)

As I omitted in the other message, the dielectric constant is not the factor to go by when choosing a coil form. It is really preferable to use a plastic with the lowest dielectric constant. The reason for this is you want the distributed capacity of the coil to be as low as possible. Capacitance in a coil stores energy, and we want the throughput to be as rapid as possible. The distributed capacitance in a coil retards the current peak that follows the VSWR (resonate rise). Coils have enough problems with distributed capacity from the length of wire, the closeness of turns, and the number of windings. No need to make things worse by choosing a plastic with a high dielectric constant.

What is most important in choosing a coil form material is the dissipation factor. The dissipation factor of all commercial plastics has been calculated, and somewhere in this mess I have those figures. If my memory serves me correctly, the standard RF dissipation factors are based on a frequency of 1 Mhz, close enough to judge if the plastic is suitable for coil work.

The next important factor to look at is the dielectric strength. This should take second place to dissipation factors if your goal is to build the most efficient coil possible. Proper con- struction, more than anything, prevents electrical breakdown.

Even if the dissipation factor is very low (good efficiency) it is best to use the thinnest wall coil form possible. Turns of wire, coats of sealer, and hard plastic end caps will stiffen the coil some. Low density polyethylene forms (such as wastebaskets) give coils with very high "Q" factors (a measure of efficiency) but are difficult to work with, as this plastic is VERY flexible.

As far as the electrical strength of a coil wound on a very thin walled plastic tube, it should not break down internally if THE WIRE IS NEVER ALLOWED INSIDE THE COIL FORM. Do not drill holes or introduce the wire into the side of the coil. A hole anywhere on the coil sidewall will cause a failure regardless of the di- electric strength of the coil form plastic. My coils are capped top and bottom with plexiglass plates that are approximately the same thickness as the coil form wall. I use two-part epoxy cement and I seal them airtight. It is OK to drill one small hole in the bottom plexiglas plate to equalize air pressure, but I do not.

The air terminal capacitance is connected by lead wire (I just use the magnet wire and avoid splicing) from the top of the coil. The lead wire is "air wound" up to the terminal, with the turns about the same diameter as the coil, or a little smaller. You will see me doing this in the video when I set up for a low power test in the garage.

The terminal capacitance must have a diameter greater than the coil form for high powered work, or spark will break out; either from the top of coil, or from the air wound turns connecting the coil to the terminal.

The other construction secret not covered in the video is the ground connection. Once the coil is wound and sealed I take the base wire and pull it up out of the sealant until it is free all the way to the beginning of the first turn. I clip off the excess wire, leaving about a 2" tail. I lay the tail on a metal block, and using a small ballpeen hammer, flatten it out as best I can. A strip of copper sheet about 3/4" by 2" is then cut from stock and bent slightly to match the curvature of the coil form. Solder the flattened tail to the back of the copper strip. Position the strip on the coil form just below the bottom turn of wire, and scribe a rectangle through the sealant all the way to the coil form plastic. Remove the sealer from the scribed area, then score and clean the bared plastic. I then use epoxy to bed the copper strip. This forms a high current grounding plate without drilling. Ground wire or strap (preferred) can be held in firm connection to the plate with tape or a large rubber band.

… And if all else fails… Put another megavolt through it

… If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 683 Date: 11-11-93 11:05 From: Dave Halliday To: Mark Lawton @ 930/20 Subj: 10kva tesla coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ ML>RQ> GD> Well I have a Jacob's ladder on an old theatre marquis neon >RQ> GD> transformer. Really makes the kitty stop and pay attention. >RQ> GD> Worries people who see it, too. My inner Beavis loves it. >RQ> >RQ>Yeah, I have some videos of the pole pig settin on the garage >RQ>floor with 3/8" copper pipe rails. Pulls arcs clear to the ML>Love it… Pole Pig = Jacob's Ladder ML>PS Does anyone need some neon transformers? I've got 3 collecting dust. >(2) 7500V & (1) 15000V Hi Mark - I just got a copy of Richards video ( well worth the $10 ) and the Jacobs ladder is fantastic! He is using 1/2" copper pipe for the electrodes and getting about a foot-long arc at the end of it. Has a wonderful "fat" sound to it too - not the bzzzzzt of a sign transformer - more of a deep growl… I saw in your previous ms. that you also are into coil building. I built a few a while ago and will be working with two other people to do a couple of them - small one ( 3' or so ) for now and maybe a >big< one down the road. TTYL - Dave ë:-) b QMPro 1.51 b ®bb<——— Š££££££ "Hmm, the force is strong with this one" -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 672 Date: 11-11-93 16:35 From: Brian Mcmurry To: Richard Quick Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ On Sun 7-Nov-1993 4:14p, Richard Quick wrote: RQ> These units must be run with a heavy RQ> current limiter or they will pull the entire neighborhood into RQ> your experiment. You should be able to energize them without RQ> dimming the lights. I've been following all the Tesla threads and wonder what your monthly electric bill runs. :) BTW, keep it coming. -!- ! Origin: *AACHEN* 818-972-9440 Burbank, CA FIDONET (1:102/844) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2755 Date: 11-11-93 17:08 From: Richard Quick To: Robert Taylor Subj: Re: 10KVA TESLA COIL ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Robert Taylor to George Powell ⇐- > using neon xformers.. GP> Do you have any probs with the xformers heating up after a GP> while? RT> To be honest–has been a while since I've had my xformers to RT> play with. But as I remember, the Jacob's Ladder hook-up RT> didn't cause any unusual overheat. You might check the size RT> of your initiating gap at the bottom of the ladder. If it's RT> too close–it will put extra strain on the xformer. Nope, it will not make any difference. The gap at the bottom of the rails can be closed and the xfrmr will not be subject to any extra strain. If the rails are properly set, the gap will be pretty close. RT> One thought–if your xformer is in a small case, the RT> overheat may be natural. Even in a big case the heating is normal. A bigger case means it takes longer for the heat to get to the point where you feel it. RT> The ones that I used were fairly big monsters that weighed RT> in at about 20 lbs. If yours is in a case about 5" high by RT> about 10" long–then yours may be prone to overheating. It's not "overheating", it's normal heating. Unless the tar is melting, or output is diminished, there is no problem. RT> However, if you have any questions as to your coil's RT> integrity try using a VOM or continuity tester on both the RT> secondary & primary & the case to make sure that there are RT> no obvious shorts. A serious overheat can really test your RT> fire insurance. Doubtful, the secondaries can be shorted without any harm, and no overheating will result. Shorts through the tar potting form carbon tracks which are high in resistance and may not be detectable with a VOM. And since these xfrmrs are magnetic leakage shunted in the core, a short in a HV winding will basicly cut the secondary out of the field flux generated by the primary. The best way to test these suckers is to grap some HV rated wire and draw an arc from each HV bushing to the case. If the arc sputters, is weak, nonexistant, or intermittent then the core should be unpotted and the winding replaced or restored. As I mentioned in another post, about half the time unpotting alone will cure a carbon track short. RT> You might also want to hook your VOM up on the primary side RT> & monitor your current draw (should be some specs on the RT> case as to 120 VAC draw). If you see way-out draws or if RT> the draw starts up w/time–then you may have a problem w/ RT> the windings. If you go by this then every unit tested will show a problem unless they were power factor corrected at the factory. The plate specs give the OUTPUT wattage, output voltage, and output current in miliamps. If you measure the input power vs. the output specs you will find 50% of your input energy missing. The unit gets hot…. You will lead Mr. Powell to believe there is a problem in the core when that may not be the case. Due to the design of the core this is completely normal. Fully one half of the input power is converted to heat eventually, as energy is bypassed through the core shunts to limit the output. Unless the xfrmr is getting hot enough to melt the potting, or the output is markedly diminished, there is no problem. If tar is melting, then the most common problem is a shorted primary winding. I have unpotted dozens of these transformers, and my experience covers every major manufacturer. I have seen nearly every problem that can cause failure, as I only rebuild failed units. I have experimented with the effects of altering the core shunts for greater output, and I have experimented with power factor correcting in these units. I have done testing to measure the efficiencies, and have developed proceedures to improve these efficiencies. In other words I know these cores backwards and forwards. Mr. Powell may not have much experience with magnetic leakage controlled xfrmrs. He is most likely interperting the normal heat production as a problem. A normal step up xfrmr weighing 10 lbs, with a throughput under a kilowatt, would not get warm. The normal step up xfrmr is not shunted, and wastes very little energy. Yet the neon gets quite warm with throughputs of only a third of a kilowatt. The neon is a different breed, and produces as much heat as output. I hope I have set the record straight. If you doubt my analysis, please unpott a neon core, and look at the physical placement of the shunts. You will wonder how any magnetic flux at all can get to the secondary windings. The shunts are positioned so as to place a direct magnetic bypass that completely surrounds the primary. It is in effect, a built in magnetic short circuit. The field flux passed through these shunts is wasted energy, and the wasted energy heats the iron core. If you have a 360 watt neon core, no power factor correction, and no core modifications, you will get about 360 watts of heat if you put a Jacob' Ladder or Tesla coil on it. 360 watts of heat will bring the core temp up quickly and it will stay quite warm to the touch. Yet everything is working fine, except for your efficiencies. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ

Msg#: 2792                          Date: 11-12-93  14:56 
From: Richard Quick                             
  To: Dave Halliday                             
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Dave Halliday to Richard Quick ⇐-

DH> Hi Richard - again, thanks for the fantastic video!

RQ> Larry J. Rebman > The Transformer Bank, Inc. > University Technology Center > 1313 Fifth St. SE > Minneapolis, MN 55415

RQ> Tel: (612) 379-3958, Fax: (612) 379-5962

DH> GREAT!!!!!

>The retail cost is a little over $1.00 a pound, so figure a 230 >pound, 10 KVA xfrmr, will run about $250.00.

RQ>The Transformer Bank has a shipping contract with RQ>Consolidated Frieghtways

RQ>My pole pig ran $303.00, including shipping, and was

 >delivered to me ten days from the date I dropped the 
 >certified check in the mail. 

Your shipping rate may be higher since you are all the way cross country, and your delivery time will most likely take longer. Still, where else are you going to go?

RQ>The unit came with certification papers that match the serial

 >number on the plate, showing it to be PCB free. 

DH> This is exactly the info I have been looking for!

Having been there I pretty much know the score. I looked for over a year for a supplier for these units, while the utilities educated me on the EPA requirements. Do not accept a pig, even a free one, if it does not have PCB certification papers. Some pigs I have seen will carry a PCB free cert. number on the plate, and that too is OK. You can then write the manufacturer and they will mail the papers if you provide them with the number.

It is not the PCBs that bother me. The problem occurs if you want to sell or dispose of the unit. With current regulations, and lack of certification, you have a legal hot potato that can cause you problems. I have not seen the letter of the law, but the utilities have informed me the legal implications are rather severe, and place serious liablities on the owners of pigs containing PCB.

There are a few transfer yards that have clean room holding facilities. They are expensive to own, maintain, and operate, but they are licensed to drain the old oil, rinse the cores, and scrap them. Cores can be purchased for a few bucks ($5-$20). The problem is that the cores are old, frequently damaged, or contaminated with water (from sitting in the rain) and won't hold up unless they are dried, repaired, and resubmerged in xfrmr oil. Better off to pay a little more and buy a surplus new unit.

Another type of xfrmr excellent for coil work is the potential type xfrmr. These are potted in plastic, not tar, and are not shunted like neons. They carry the HV ratings required, and/or can be placed in series (two 7500 volt units for a total of 15KV). Since the cores are NOT shell wound, they will saturate, and so they are safer and require little or no current limiting. These xfrmrs may be obtained from utilities without the problem of EPA regs. The normal ratings on potential xfrmrs runs from about 1-3 KVA, and so are ideal for the middle area between neons and pole pigs. The surplus cost on these runs from $25.00 - $50.00 each, but they will be used, not new, surplus.

These xfrmrs are used to step down a kilowatt or two for cooling fans, and for line voltage sensors in substations; so they are not manufactured in the quantities that pigs are. They are much harder to find in the surplus market, but definately worth grabbing if you come across one. If you developed any contacts at the local utilities while searching for a pig, you might call them back and ask them about potential transformers.

DH> I also got your postings on neon sign transformers yesterday DH> - the idea of getting the reject units from a sign company DH> is obvious - should have thought of that one… <WHACK!> DH> ( sound of head hitting desk )

Yeah, neons are not built very solid. The secondaries are el'cheapo, as the thinnest wire possible is used. The failure rate is pretty high even in their rated service. Since the copper content is low, they are not commonly recycled, and the cores pile up quickly. The higher the output current rating, the better they are built. Once the tar potting is removed, they last much longer in Tesla use. Tar is a very poor RF insulator. To a Tesla discharge, the tar looks more like an impedance! Pick up dead units for nothing, remove the tar, modify the core slightly, and use pfc capacitance; then they will serve cheaply and effi- ciently. You must use heavy RF choking, safety gaps, and bypass capacitors if you want more than a few hours of heavy duty service from a bank of neons.

As far as RF choking is concerned, the HV filter board I designed and built in the video is the best I have ever used. I have not had a single xfrmr failure since I built it. Bypass capacitors on neon power supplies must be center tap grounded, so I switch to using a different capacitor setup. As the secondaries on neons are center tap ground, so must the bypass capacitors. I use two stacks of caps; each stack has a connection to a HV bushing, and to the system ground.

… And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 654 Date: 11-12-93 16:57 From: Richard Quick To: Guy Daugherty Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>a real lab. RQ>The building so far is looking like this: RQ>50' x 60' with 8' masonry walls and 8' sheet metal walls on RQ>top. This gives a total wall height of 16 feet, with a slope RQ>up to the center of the roof for a 20' peak. GD> This is geting out of hand, Richard. Well Guy, I need a place to put all of my stuff where it won't get rained on. Any other bright ideas? I have about $5000.00 worth of Tesla equip. ($15,000 replacement cost), about $5000.00 worth of chemistry equip, not to mention boxes of homemade pyrotechinics equipment (ball mill, star presses, rocket ramming table, drying racks, rolls of paper and tubing, mixing containers, sieves, etc.) I also buy, sell, and build/rebuild/repair Vespa scooters; own three now, plus parts of a forth, plus a workbench of special tools for engines, frames, wheels, etc. I would like to mess around with some hard vacuum equipment, and do some bulb blowing/tube bending… and I need a place to put my shop tools (band saw, drill press, belt sander, table saw, air compressor, etc.) Then I need an office (some place other than my bedroom), where I can put my $5000.00 worth of computer equipt., desk, and library, and what do I do with my 55 gallon fish tank? The AV equipment? Where do you suggest I go with all of my toys? I would like to house everything somewhere where I don't disturb people, I can work day or night at will; blow things up, burn things out, and set up and fire some big coils, and all will be safe. … Do you need a roomate? Is it OK if I experiment nextdoor? My "eccentricities" core my very being. I have a temporary "block house" out in the back drive where I mill powders, but I worry about vandals having their tables turned on them, or some innocent kids investigating the grinding noise and accidently blowing themselves off the property. I retained a shipping/ receiving agent some years ago, and he will tell you that I get the most bizzare packages he has ever seen… BTW I don't think I require professional advice on how to spend money, I learned just fine, and I know exactly why I get up and go to work every day. My priorities are different than most people, and so are my needs. This building is not an extra- vagance. It is already filled, and I will probably have to add an additional storage building within the first couple of years or so, then I imagine I will have to add another building to move out my shop equipment to keep the floor space clear in the main lab area. What would you do? … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 12 Nov 93 22:49:34 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ * Originally By: Richard Quick * Originally To: Guy Daugherty * Originally Re: 10KVA Tesla Coil * Original Area: FIDOElectr * Forwarded by : Blue Wave v2.12 RQ>a real lab. RQ>The building so far is looking like this: RQ>50' x 60' with 8' masonry walls and 8' sheet metal walls on RQ>top. This gives a total wall height of 16 feet, with a slope RQ>up to the center of the roof for a 20' peak. GD> This is geting out of hand, Richard. Well Guy, I need a place to put all of my stuff where it won't get rained on. Any other bright ideas? I have about $5000.00 worth of Tesla equip. ($15,000 replacement cost), about $5000.00 worth of chemistry equip, not to mention boxes of homemade pyrotechinics equipment (ball mill, star presses, rocket ramming table, drying racks, rolls of paper and tubing, mixing containers, sieves, etc.) I also buy, sell, and build/rebuild/repair Vespa scooters; own three now, plus parts of a forth, plus a workbench of special tools for engines, frames, wheels, etc. I would like to mess around with some hard vacuum equipment, and do some bulb blowing/tube bending… and I need a place to put my shop tools (band saw, drill press, belt sander, table saw, air compressor, etc.) Then I need an office (some place other than my bedroom), where I can put my $5000.00 worth of computer equipt., desk, and library, and what do I do with my 55 gallon fish tank? The AV equipment? Where do you suggest I go with all of my toys? I would like to house everything somewhere where I don't disturb people, I can work day or night at will; blow things up, burn things out, and set up and fire some big coils, and all will be safe. … Do you need a roomate? Is it OK if I experiment nextdoor? My "eccentricities" core my very being. I have a temporary "block house" out in the back drive where I mill powders, but I worry about vandals having their tables turned on them, or some innocent kids investigating the grinding noise and accidently blowing themselves off the property. I retained a shipping/ receiving agent some years ago, and he will tell you that I get the most bizzare packages he has ever seen… BTW I don't think I require professional advice on how to spend money, I learned just fine, and I know exactly why I get up and go to work every day. My priorities are different than most people, and so are my needs. This building is not an extra- vagance. It is already filled, and I will probably have to add an additional storage building within the first couple of years or so, then I imagine I will have to add another building to move out my shop equipment to keep the floor space clear in the main lab area. What would you do? … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 13 Nov 93 00:42:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Looking over my last post, I can anticipate a few questions. I described a very poor grounding system. What then makes a good RF ground? Well a small coil can fire off a radiating counterpoise (insul- ated metal plate) a few feet square. But when you overload a counterpoise, you get a really wicked corona display, and the coil will produce no additional spark. Having set up various experiments to study this effect, including tracing the ground current, and using a current transformer to measure the RMS amps coming from the base of a Tesla secondary, I can tell you this. There is no such thing as a RF "system" ground that is too heavy. Not in Tesla coils. This is another thing that Tesla went on and on about. But my follow up experiments in this area, which have been quite extensive, show that he knew what he was talking about. I got extremely lucky in that we have a hydraulic car lift in our back driveway. There is a 5' steel cylinder that is 14" in diam.. In addition to the giant piston, there are buried oil and air tanks with all of the associated plumbing. The lift controls are sunk right where the house foundation drains, and it is in the lowest spot in rear of the house. There are no electrical connections made to this lift, air being supplied when needed by a hose. This is my Tesla ground. A good Tesla RF ground is usually developed, not happened upon. It will require some digging and post driving. It needs to be kept moist. Drive deep with copper pipe, or copper clad rod, and keep adding to it. Metal culverts, metal sewer drain pipe should be connected if available. Spread out! Do not drive rod or pipe close together. Four or five 8' rods driven in a long row, 8' apart will work. A ground that you are absolutely sure will ground a bolt of natural lightning, will be heavy enough to ground most coils. DON'T CHINCH! People have asked me if I get complaints about RFI. The answer is no. The reason is that I isolate my coil (system) ground from the copper water pipe and from the utility ground (which in my house are the same). Here is a basic list of things that you DO NOT CONNECT to the system RF ground: WATER PIPE, GAS PIPE, UTILITY GROUND, ANYTHING THAT STICKS UP IN THE AIR (fences, gutters, downspouts) TELEPHONE GROUNDS, & CABLE GROUNDS. Most anything else is fair game, but use common sense. You build or find a heavy ground and you ground your coil system to it. The connections made to this RF ground are as follows: SECONDARY COIL, SAFETY GAP, STEP UP XFRMR CORE, BYPASS CAPACITORS (if using a center tap grnd xfrmr), SPARK GAP MOTOR HOUSINGS, SPARK SHIELDS, AND ANY OBJECT SUBJECT TO BE STRUCK WITH DISCHARGE I don't usually use my caps lock, but this is important. This technique prevents RFI complaints, and will save valuable electronic equipment in your area from destruction. It may save you from the last shock of your life. You ground your variac housing to your neutral wire. All other coil controls, relay housings, control xfrmr cores, line RFI filters (run backwards) are grounded to the variac housing. Strap is taken from the variac housing to a well grounded water pipe. This protects the coil operator and the control circuits from kickback that may come down the line from the step up xfrmr. Two 60 cycle cables are run from the variac, through reversed line filters, out to the step up xfrmr. No ground connection is made anywhere between the 60 cycle cabinet ground and the RF system ground. Hot wires only are given to the primary of the step up xfrmr, as well as any gap motors or other utility for the coil tank circuit. This is called the "two ground system" and it is highly recom- mended. The idea of the two ground system is to send all of the RF to a dedicated ground, and prevent bleedover into your house wiring, control cabinet and/or water pipe. It also protects the operator with two low potential grounds from the lethal possi- bilities of a coil misfire or similar "incident". People have told me I am crazy for messing with all of this HV. I take NO CHANCES with my ground. The ground strap is literally the "bottom line" in coil safety or any other HV apparatus. If an accident occurs; a core shorts out, a capacitor blows, or the secondary decides to dump a 10' spark back to the tank circuit; I know my safety gap - RF ground will handle the load. My 60 cycle cabinet ground is my backup. With tank circuit energies in the megawatt range you can't afford to have a weak point. Keep the physical distance between the base of the secondary coil and the system RF ground as short as possible. I try never to go further than 20 feet for low power stuff, and 15' or less for the high powered work. Use the heaviest strap possible. I run two heavy straps; one from the base of the secondary directly to system ground, the second snakes around and grounds everything else. This is a high Q Tesla grounding system. It gives the best coil performance, the most safety for the coil operator, and guess what? People in my house, and the neighbors next door, can watch TV or listen to the radio, with no snow or static! Even during high power operation! I never get spark from my coil controls. All of the RF currents that are not expended in spark are directly, positively, grounded through a high Q ground path to a high Q ground that is electrically isolated from all other equipment. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12

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Msg#: 2932                          Date: 11-13-93  10:43 
From: Dave Halliday                                 
  To: Richard Quick                                 
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> RQ>The building so far is looking like this: RQ> RQ>50' x 60' with 8' masonry walls and 8' sheet metal wallson

> RQ>top. This gives a total wall height of 16 feet, with a slope 

RQ> DH> WOW! Do you plan to do shows? You could charge admission. RQ> DH> Sounds fantastic!

RQ>The thought has crossed my mind. The primary use of the structure

>would be of course R&D of the Magnifier on a medium scale, but 
>rest assured it will see other uses as well. With room for 
>storage, permanent set-ups, etc. Shows would be a snap to do. 
>Not many people have seen the old Million Volts Through The Body 
>trick, and it is a thrill to do, as well as to see. 

I grew up in Pittsburgh PA and the local Planetarium there had a coil that they gave public demos on - I do not know any of the actual data on it save that it was about 7-10 feet tall, large solenoid primary of about 10 turns with a tap on it and that it really caught my attention every time it was set off <grin>

Anyway, I just got a bunch of material from you so I will print it out and read through it. I did get your post on Neon Sign transformers and the other people are also interested in starting small but I also got the info about that place that sells GE surplus pole pigs too so we should be ready for that too!

Thanks for the clarification re: the Schedule 40 pipe - I had always looked at it as being heavier so therefore "better" - never thought of the actual material as being a liability. What about ABS - is there any difference with that?

Anyway, we will probably do a couple capacitors in the next week or so. Like I said, I have an OK vacuum pump ( I do graphic arts and printing ) and can pump it out so that should improve things.

Anyway, many many thanks for your time and help!

TTYL - Dave ë:-) b QMPro 1.51 b "Oxymoron": A really, really, dumb baby ox…

-!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546)

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Msg#: 852                           Date: 11-13-93  12:34 
From: Guy Daugherty                         
  To: Richard Quick                         
Subj: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> RQ>50' x 60' with 8' masonry walls and 8' sheet metal walls on

RQ> GD> This is geting out of hand, Richard.

RQ>Well Guy, I need a place to put all of my stuff where it won't RQ>get rained on. Any other bright ideas?

Yeah, but the perpetual motion thing with the generator driving

  the motor driving the generator isn't working the way I thought it 
  would. 

RQ>I have about $5000.00 worth of Tesla equip. ($15,000 replacement RQ>cost), about $5000.00 worth of chemistry equip, not to mention RQ>boxes of homemade pyrotechinics equipment (ball mill, star RQ>presses, rocket ramming table, drying racks, rolls of paper and RQ>tubing, mixing containers, sieves, etc.) I also buy, sell, and

No. Richard, you're NOT building fireworks, too? STOP IT!!

RQ>build/rebuild/repair Vespa scooters; own three now, plus parts of RQ>a forth, plus a workbench of special tools for engines, frames, RQ>wheels, etc.

Not much surprise there, really…..

RQ>I would like to mess around with some hard vacuum equipment, RQ>and do some bulb blowing/tube bending… and I need a place to RQ>put my shop tools (band saw, drill press, belt sander, table saw, RQ>air compressor, etc.)

RQ>Then I need an office (some place other than my bedroom), where I RQ>can put my $5000.00 worth of computer equipt., desk, and library, RQ>and what do I do with my 55 gallon fish tank? The AV equipment?

RQ>Where do you suggest I go with all of my toys? I would like to

Oh, no, Richard. Don't EVER leave the door open like that.

RQ>house everything somewhere where I don't disturb people, I can

I'm kinda worried about how you're disturbing yourself….

RQ>work day or night at will; blow things up, burn things out, and RQ>set up and fire some big coils, and all will be safe.

You need a concrete-lined pit.

RQ>My "eccentricities" core my very being. I have a temporary "block

Not me. Completely nnnnormal, here. Honest. My neighbor's dog

   will attest to this in court. 

RQ>house" out in the back drive where I mill powders, but I worry RQ>about vandals having their tables turned on them, or some RQ>innocent kids investigating the grinding noise and accidently RQ>blowing themselves off the property. I retained a shipping/

Just desserts.

RQ>receiving agent some years ago, and he will tell you that I get RQ>the most bizzare packages he has ever seen…

We take your word for it…..

RQ>BTW I don't think I require professional advice on how to spend

Oh, I'm just amateur. Haven't made a cent at it, yet….

RQ>money, I learned just fine, and I know exactly why I get up and RQ>go to work every day. My priorities are different than most RQ>people, and so are my needs. This building is not an extra- RQ>vagance. It is already filled, and I will probably have to add an RQ>additional storage building within the first couple of years or RQ>so, then I imagine I will have to add another building to move RQ>out my shop equipment to keep the floor space clear in the main RQ>lab area. What would you do?

Ummm…. place a palm against each temple and repeat "Oh, no!" a

   dozen times? 

-!-

 SLMR 2.1a    But when the first shot hit the dock, I started 

runnin'

-!- GEcho 1.00 ! Origin: The Silhouetter bbs (209)472-0843 USR DS 16.8K (1:208/216)

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Msg#: 2826                          Date: 11-13-93  13:26 
From: Richard Quick                     
  To: Brian Mcmurry                     
Subj: Re: 10KVA Tesla Coil 

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ BM> On Sun 7-Nov-1993 4:14p, Richard Quick wrote:

RQ> These units must be run with a heavy current limiter or they RQ> will pull the entire neighborhood into your experiment. You RQ> should be able to energize them without dimming the lights.

BM> I've been following all the Tesla threads and wonder what BM> your monthly electric bill runs. :)

BM> BTW, keep it coming.

Thanks, another vote of confidence. Much appreciated.

Well it's not as bad as it sounds. Tesla had one god: EFFICIENCY!

If you follow his work, you will find that efficiency is what makes his systems beautiful, they don't waste much.

At one time I hooked a standard electric company wattmeter up to the 240 V 100 A single phase supply circuit that I am using at this time. Over a period of a month or so I used about $20.00 worth of electricity to actually fire coils.

There are other circuits that I tap to provide utilities to the coils. Some of my spark gaps use compressed air to quench, others use 240 volt vacuum motors, yet another uses muffin fans, I also run a rotary gap motor in combination with a static gap on all my bigger stuff for better efficiency and performance. These utilities might use 25% of the energy I put into the coil, so add another $5.00. I would feel comfortable saying $25-$30 a month.

Even when I run a big coil at 8-10 KVA I don't leave it running all night. Five or six runs of between 3-8 minutes each is enough to satisfy me, give me the data I need to improve, and get some good video.

I don't fire every night. It is much more fun to have company over and have a friend video tape the coils in action. The big stuff has to be fired outdoors since I don't have the ceiling height or floor space to fire anything bigger than an 8" coil indoors. Outdoor firing is weather and neighbor dependant. I have had some bad luck firing coils in windy conditions, and the neighbors have threaten to get their torches and burn me out if I fire too late at night (spark gaps sound like unmuffled chainsaws at this power level).

The pole pigs used in heavy work are over 95% efficient, but current limiting, depending on type, can waste 50% of your input energy in the form of heat. In every area of my work I have pushed the edges of my efficiencies, just as Tesla would have. I use efficient step up power supplies to drive the oscillators, with efficient: current limiters, tank circuits, capacitors, spark gaps, etc.. With neons power factor correction helps a lot.

The goal in 1/4 wave coils is to turn every watt possible into discharge, and waste as little as possible between the wall and the discharge terminal. I am very good at it, and I believe I am holding record spark lengths for input powers. If I do not hold records, then I am very very close, but I have not seen any system outperform mine up to 10KVA. And there is still room to do better with my 1/4 wave coils.

To give you an idea, my power processing efficiencies range from 460 to 1100 watts (power drawn from the wall), per foot of spark generated on my large coil. These figures are not linear, as I am not using a sychronous rotary spark gap. The average strike from the coil will reach anywhere from nine to eleven feet at 5-8 KVA. But have seen more than a few 15' strikes at powers under 10 KVA.

… And if all else fails… Put another megavolt through it

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Msg#: 2933                          Date: 11-13-93  15:17 
From: Dave Halliday                               
  To: Richard Quick                               
Subj: tesla coils      

ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Hi Richard - I have had time to go through and read the stuff you posted - thanks again for the time you are spending here - this info will be not only a great help but also a great motivator.

I had thought about getting back into Tesla coils for some time and it took seeing what some one else out there was doing it to get me started <grin>

DH> Very interesting that so much of the energy from it could be DH> so closely coupled to the second coil… This will be a fun DH> winter project!!!

The "extra coil" is completely uncoupled from the driver system. Current from the driver is being fed into the base of the free standing "extra" coil by transmission line. While you are not able to see in the video… The transmission line glows with corona from the heavy current.

I figured that it was not part of the primary / secondary circuit but got it's power through the wire off of the Tesla secondary.

Amazing stuff and definitely the next thing to try after building the first coil.

DH> I was talking with one of the people and they agreed to DH> start on a smaller coil - I was thinking in the order of 4" DH> diameter and about 3' long.

The aspect ratio (height to width ratio) is important. The planned coil has an aspect ratio of 9:1 (36" long, 4" diam.) this should be reduced to no more than 5:1 on a 4" diam. coil. 6" coils work best with 4:1 aspect ratio, anything larger 3:1.

(cut from another part of a post)* The coil should be wound with good quality magnet wire. I use double Formvar enamel coated magnet wire. Magnet wire gives you maximum inductance. A coil should have over 900 turns, but not too much over 1000 turns. There is a little leeway here. Select a gauge of wire which will allow the aspect ratio and number of turns to fall within this range. OK - I made an "editorial decision" today to go for a 6" diameter form and make it 24" long. I just was out running errands and got 1,500' of 22 gauge Heavy Formvar insulated magnet wire so with a diameter of 0.0253, this works out to 948 turns - right in the ballpark that you suggested in another part of this post. I think the other people were thinking in the realm of the normal misconception of Tesla coils as being long and skinny but I guess that would make them longer than 1/4 wave… We'll see what happens! Vacuum Spark Gap the video, but once it was working, it worked great. It has trouble at power levels over 5 kVA. After an evening on the big coil at 8 to 10 kVA I had some pitting and melting of the electrode faces. This was reduced as I cut back on the number of electrodes, increased the size (both length and diam.) of the electrodes, and allowed for a larger gap between electrodes. OK - I wonder if it would be feasible to make it with continuously variable gap size - something with threaded plastic rods… I think that since we are starting with neon sign x-formers, we can just use the standard 6" PVC gap you showed - aren't going to be running too much power through it <yet> These homemade capacitors are high Q, reliable, and relatively easy to build. Pumping them down will really help. As I said - I do printing as well as the electronics and computers and every piece of equipment here ( almost ) has some kind of vacuum pump associated with it. These are all rotary-vane types so not really high Torr but should be OK for "potting" the caps in oil. DH> You mention that PVC is better but you also say not to use DH> Schedule 40 - both kinds of pipe are rated as being Schedule PVC is the worst plastic for use in secondary coils. It is "lossy" (high RF dissipation factor) and has a low dielectric strength. But it is commonly used because, as you mentioned, it is available. Coil forms, regardless of material, should be as thin as possible. Schedule 40 is thick, and is rated for pressure use. Try to locate the thinner "drain" pipe or "flume duct" PVC or other thin wall plastic. If PVC is used, it MUST be dry (baked is preferred) and well sealed with a low loss sealant like poly- urethane or two part epoxy. OK - there is some pretty thin wall stuff in our local "Home Center" store - I was worried about mechanical strength though - I can deflect this pipe with just moderate pressure - I will have to stop into the Cadillac Plastics store and see what they have in their cut-off's bin… Also, I have a small South Bend lathe and could probably get Schedule 40 and then turn off a bunch of it until it got too thin… Baking it and then sealing it is a good idea - I will probably use the slow speed on the lathe to wind the coil so I could also turn it slowly while I was applying the sealer - keep it drip-free… A combination of dielectric strength, and the RF dissipation factor. PVC fails this test, and requires drying and sealing to make it suitable. Teflon is the best; good dielectric strength, and the lowest RF dissipation factor; then comes polyethylene, polystyrene, and polypropylene, all of which are good. The same When I was getting the wire, I made the mistake of pricing teflon insulated wire. That would be a coil that shocks people twice. You spent ??HOW?? much… <grin> You asked about power supplies: The pole pig info is on it's way. See my two part post on obtaining neons for free, and rebuilding them for high output, high efficiency, Tesla power supplies. I got both sets of info - the guy you recommended was out hunting but will be back on this Monday - they knew about Tesla coils though and recognized your name… Remember Tesla power supplies must be protected with extensive RF choking, and safety gaps. This is especially important with neons, which are much more delicate than pole pigs or potential xfrmrs. I also use bypass capacitors. For bypass capacitance across the power supply HV terminals you WANT a dielectric with a high RF dissipation factor. Barium titanate capacitors with a DC rating are ideal for this use. Use a 4x voltage safety factor. Got it - the insulation of the neon is only meant to handle 15 KV, not whatever the coil is putting out… I have a bunch of largish ferrite torrids so I'll use them and a spark gap. The other construction secret not covered in the video is the ground connection. Once the coil is wound and sealed I take the base wire and pull it up out of the sealant until it is free all the way to the beginning of the first turn. I clip off the excess wire, leaving about a 2" tail. I lay the tail on a metal block, Great idea - high current, low impedance and quick connection. Anyway, this message is kind of chopped up, I saved your posts and then just went in with Q Edit and edited and added replies but you should follow who is talking… Again - thanks for your time and info - I'll have to send you copies of the pictures once we start building this puppy! TTYL - Dave ë:-) b QMPro 1.51 b True Multitasking - 3 PC's and a chair with wheels… -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 13 Nov 93 19:17:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Tesla "Q" Factors Since some people are saving these posts to disk, and at least one other person (Dave Halliday) is going to embark on some coil building. I thought I would take a moment and discuss some Tesla theory that directly relates to coil efficiencies. The subject is the "Q" factor. Q is literally the "Quality" factor. There is no real way to calculate Q in a subassembly, assembly, connection, or component in a Tesla coil. But Q exists. Q in a secondary coil can be calc- ulated from the physical coil data after it is wound, but with most coil parts it is more like a "god". Some people dedicate their lives in search of god, coilers dedicate their lives in search of higher Qs. The Q factor of any Tesla component is a combination of material, design, and construction. A coiler never reaches near theoretical Q factors. We don't wind our coils out of high temperature super- conductors and fire them submerged in liquid nitrogen. Indeed people hardly ever submerge their coils in oil like in good old days. Oil submersion is probably the single greatest thing you can do to raise the overall Q factor in any Tesla coil system. In the old days they almost had to submerge the coils in oil to regain Q that was lost in the use of "classic" materials such as wood or cardboard coil forms, rubber or tar insulators, silk or cotton covered wire. These "classic" construction materials are inherently low Q and result in designs and construction techni- ques that are also low Q. Builders tolerated oil leaking wooden boxes and greasy cabinets in many cases to get a good spark. We live in an age of high Q materials and construction techni- ques. I have mentioned some of the most commonly used materials in several posts, but I will list a few again. Teflon, polyethy- lene, polystyrene, polypropylene, acrylics, epoxy, hot glue, enamel and polyurethane sealers. As well as the all time classic high Q corona suppressant, mineral oil. Modern coils had to be redesigned in order to take advantage of these new materials. These modern designs differ in many ways from a coil using "classic" low Q materials. Secondary coils can be close wound with magnet wire rather than space wound with insulated wire. Primary coils can be tighter, placing higher inductance into a smaller area. Coupling can be increased dramatically, even in 1/4 wave systems, by using corona sup- pressing sealers and toroid discharge terminals. The coils get smaller, more powerful, and more efficient. Building high Q systems means we can live without things like oil submersion, and still get better spark. With these higher Q systems it is more economical to put additional capacitance and heavier power supplies on line to increase spark than it is to struggle getting the system Q closer to ultimate theoretical. Theoretical Q can go to infinity. So when you are designing, hunting materials, and building; always keep an eye on the Q factor. Attention paid to many little areas adds up to substantially higher overall system Q. A solid ground, tight clean connections, close wound and sealed secondary, primary coil of high Q material wound on a high Q plastic form, well aligned gaps that quench, plastic film HV pulse discharging capacitance, and toroid dischargers are some of the major factors in the overall system Q. Experiments in a variety of Tesla systems shows that the overall Q of the system is limited by the lowest Q component used. The old expression "The chain is as strong as its' weakest link" applies. One area that is frequently neglected by Tesla coilers is the Q of the system RF ground and the ground path. Since coil systems are built from the "ground" up, this is the first thing a good coiler will look at when he goes to set up and fire a coil. I know a guy in New York who fires at about the same power levels as I do. My coil systems are much higher Q and I get much better spark using less energy with a smaller coil. When I took a close look at his coil setup, I noticed he was grounding his coil system to the neutral wire in the breaker box. Walking outside, I traced the ground path to a single 3' copper plated rod driven in by the utility company to ground the supply xfrmr to the building. This is completely inadequate for high powered Tesla work, and is quite unsafe. I also noticed that this guy had a newly constructed all wood power control cabinet. Now there is nothing wrong with that as long as it is well wired with ground strap, which it wasn't. But out back I could see a nice metal control cabinet that had been recently gutted. When I inquired, he stated he had to switch to an ungrounded, wooden, control cabinet because he was drawing sparks to fingers when he touched the controls… The paced distance from the base of his secondary to the 3' copper clad ground rod was slightly over 75'. Most of the distance was traversed with #10 wire. No wonder when he grounded the cabinet and touched to controls he drew spark, his ground path had a high RF impedance, and was backing up like a clogged toilet. I tactfully offered some advice, which was refused. Obviously he had spent a lot of effort compounding his mistakes, and had no desire to let someone else point them out. Don't make the same mistake. Be efficient and safe. Ground properly from the very start. Think Q! -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 839 Date: 11-14-93 20:22 From: Joseph Worthington To: Guy Daugherty Subj: 10kva Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ The thread on the Tesla project is very interesting! If you are the moderator, please let it go on for a while. Joseph -!- ! Origin: The Bunker—Eugene, OR (503) 345-2429 (1:152/11) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 886 Date: 11-15-93 22:45 From: David Tiefenbrunn To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Hello, Richard. I have sent you a video tape. I hope the offer is still good. I included a few minutes of the first run of the 45KW generator. The new lab sounds great. Of course, you will probably get the tape before this message. :) Dave _ * OFFLINE 1.54 * I love the smell of ozone in the morning. -!- Maximus 2.01wb ! Origin: =Abbey Road BBS= Higganum, Ct. (203)345-7635 (1:320/5967) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 15 Nov 93 22:51:20 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Spark Gap Technology I recently explained the definition of "Q", and the requirements and functions of high Q grounding systems in Tesla coils. Another area that needs attention is spark gap technologies. Spark gaps are the "brain" of the Tesla Coil. They are high the voltage switches that allow the tank circuit capacitance to charge and discharge. As performance of the spark gap switch is improved, peak powers in the tank circuit grow without requiring additional input power. When a good coiler sets up and fires a system, the first thing he looks at is his ground. The second thing he looks at is his spark gap system. Before I cover the main points on spark gaps, I want to talk for a moment about their more modern replacements, the vacuum tube, and the solid state transistor (FET etc.). Both modern day replacements can be made to function in Tesla type oscillators in several modes. A single resonating coil may be base fed RF current from solid state and tube drivers, or primary coils may be driven with amplifier circuits. Class C amplifiers are preferred. Both of these modes work well within the power handling abilities of the switch (tube or solid state device), but when it comes to handling raw power, nothing delivers the megawatts like the old fashion spark gap. The spark gap gives the biggest bang for the buck. No discussion of spark gaps is complete without at least a rough definition of "quenching". This term is commonly thrown around when talking about spark gaps. When I began coiling, I saw the term frequently, but never could find a good definition. Quenching refers, more than anything else, to the art of extin- guishing an established arc in the gap. The term points to the fact that it is much easier to start a gap firing than it is to put one out. In Tesla coils, putting out the arc is imperative to good tank circuit performance. A cold, non-firing, spark gap is "clean". It contains no plasma, or hot ions. On applying voltage to the gap, a tension is esta- blished, and electromagnetic lines of force form. The physical shape of the electrodes determines to a large degree the shape of the field, or lines of force, and the resultant breakdown voltage of the gap at any given distance. In other words, electrodes of different shapes will break down at different voltages, even with identical distances between them. Once the voltage punctures the air (or other dielectric gas) the gap resistance drops. The breakdown ionizes the gas between electrodes, and the arc begins to ablate and ionize the metal electrodes themselves. This mixture of ions forms a highly cond- uctive plasma between the gap electrodes. Without this highly conductive channel through the gap, efficient tank circuit oscillation would be impossible. But the plasma also shorts the gap out. A gap choked with hot ions does not want to open and allow the capacitors to recharge for the next pulse. The gap is gets "dirty" with hot ionized gases, and must be quenched. Quenching typically relies on one or more techniques. The most common method used is expending the arc out over a series of gaps. Gaps of this type are know as "series static gaps". "Static" in this use refers to the fact that the gap is not actively quenched. The plasma is formed in several locations, and the voltage at each gap is lowered as more electrodes are placed in series. Heat, hot ions, and voltage are distributed. As the tank circuit loses energy to the secondary coil, the voltage and current in the tank circuit, and likewise across the series of gaps, drops to the point where the arc is no longer self sustaining. The arc breaks, and the capacitors are allowed to recharge for the next pulse. The second type of quenching technique involves using an air blast. A high speed air stream is introduced into one or more gaps. The air stream does not alter the magnetic lines of force that cause a dielectric breakdown in the gap, so gap distance remains unchanged. But once an arc is established, the air stream removes hot ions from between electrodes and physically disrupts the established arc. The gap is swept clean of hot ions, the arc breaks, and the capacitors are allowed to recharge. A third type of quenching used is the magnetically quenched gap. A strong magnetic field is placed between the electrodes. Since this field alters the field formed by the high voltage prior to breakdown of the dielectric in the gap, it may affect the break- down voltage of a given set of electrodes. Once the gap breaks down however, the field shape changes. The high current flowing through the gap generates a field shape associated with the current. By placing a strong magnetic field in right angles to the current flow, the arc is disrupted. This disruption tears at the magnetic lines of force formed by the high current channel flowing through the gap. The arc is twisted, and broken, without having to remove ions. Another type of spark gap called the "quench gap" is used on coils designed for CW output. This gap was discussed in a previous post and will not be covered here. The next stage employed in spark gap technologies is placing a rotary gap in the circuit. The rotary gap is a mechanical spark gap usually consisting of revolving disk with electrodes mounted on the rim. The rotor is spun and the electrodes move in relation to a set of stationary electrodes nearby. As a moving electrode comes near a stationary electrode, the gap fires. As is moves away the arc is stretched and broken. The rotary gap offers the sophisticated coiler the opportunity to control the pulse in the tank circuit. A properly designed rotary gap can control the break rate (bps) and the dwell time. Rotary gaps are run in two modes, synchronous and asynchronous. A synchronous gap runs at a fixed speed and is constructed so that the gap fires in direct relation to the 60 cycle waveform of the line feed to the capacitors. The point in the waveform where the gaps are closest can be changed by rotating the synchronous motor housing or by altering the disk position on the motor shaft. By carefully matching the output of the supply transformer to the value of capacitance in the tank circuit, then running a properly set up synchronous gap, it is possible to have the gap fire only at the voltage peaks of the 60 cycle input current. This technique allows the tank circuit to fire only on the maximum voltage peaks and delivers the pulse from a fully charged capacitor each time the gap fires. If properly engineered, synchronous spark gap systems will deliver the largest EMFs to the secondary coil. They are however, the most finicky, and difficult to engineer of any spark gap, and require sophisticated test equipment to set up. Asynchronous gaps are more common. They work quite well and are much easier to run. Fixed or variable speed motors may be used, though variable speed gaps give the builder the most experimental leeway. Break rates need to be in excess of 400 bps, and I have found that breaks rates around 450-480 bps give the best discharge. Since the gap is firing more often than the 60 cycle waveform switches polarity, more power can be fed into the tank circuit, as the capacitors can be charged and discharged more rapidly. Though this system will increase the amount of spark from the secondary, sparks are generally not as long as with synchronous gaps. At higher powers (over 5 kVA) even a rotary gap will not deliver the quench times required for excellent performance unless it is very large. If the arc in the spark gap hangs too long (NOT quenched), it leaves the tank circuit electrically closed. With the gap still firing energy will backflow from the secondary into the primary and create continued oscillation in the tank circuit. The secondary is then suppling energy to maintain the arc in the spark gap. As power levels build, so does the pressure on the spark gap. Engineering more sophisticated gap systems is the only solution in large 1/4 wave coils and Magnifiers. The easiest solution at 5 kVA is to add a static gap in series with the rotary. By messing with the gap settings it is not difficult to develop a gap system that fires smoothly and quenches well. As power levels increase though static gaps will be overwhelmed. More sophisticated gaps are required to replace the static series gaps. Magnetic or airblast gaps must be used in conjunction with the rotary gap to remove the strain on the rotary and get the quench times back down. Somewhere in here I need to cover the Q of spark gaps. Not all spark gaps have the same Q. I have found that using large series static gaps with lots of electrodes; the Q of the gap system decreases as the quench time decreases! Try to avoid static gap designs with more than 6 - 8 electrodes in series. As my power levels went up, and my spark gap Qs went down, I experimented with options to regain performance. I found that by running static gaps in a combination of series/parallel gave me good quench times and I regained some lost Q from the arc having to make so many series jumps. The idea was to split the arc down into two or three equal paths, reducing the current traveling each set of series gaps. In this fashion I was able to achieve excellent quench times with a small rotary running around 5 kVA. The lesson learned was too many gaps in series kills the Q of a spark gap. By adding gaps in parallel, and reducing the number of gaps in series, some Q was regained while power levels increased. This is a valuable hint in spark gap designs. Another factor that should be brought into this discussion is the effects of cooling the electrodes. To start with, I have never run even a simple static gap without some airflow. My first few really good static gaps were constructed inside of PVC pipe sections with a 5" muffin fan on top. The fan did not supply sufficient air to disrupt the arc, but did assist in removing hot ions, and cooling the electrodes down. This allows for longer run times. As my work progressed I realized that reducing the electrode temperature, while not actually quenching the gap, reduces the amount of metal ions introduced into the arc, and makes the gap easier to quench with an airblast or magnets. I am going to cut this off here. I feel I have covered most of the basics, and thrown a few ideas out into the cyberspace. I would be more than happy to expand on spark gap technologies at any time should somebody have any specific questions, comments, problems, or corrections. Remember, armchair debate is no substitute for actually going out an experimenting with a few live systems, and I am always hoping someone will tell me a better way to do it! One final safety note. Spark gaps are loud, and emit a lot of hard UV radiation. Wear hearing protection as required, and never stare at an operating spark gap without welding goggles. To examine the arc on large coils, a sun observation filter on a small telescope will tell you if your gaps are quenching. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 773 Date: 11-15-93 22:57 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Rotary gaps are run in two modes, synchronous and asynchronous. A synchronous gap runs at a fixed speed and is constructed so that the gap fires in direct relation to the 60 cycle waveform of the line feed to the capacitors. The point in the waveform where the gaps are closest can be changed by rotating the synchronous motor housing or by altering the disk position on the motor shaft. By carefully matching the output of the supply transformer to the value of capacitance in the tank circuit, then running a properly set up synchronous gap, it is possible to have the gap fire only at the voltage peaks of the 60 cycle input current. This technique allows the tank circuit to fire only on the maximum voltage peaks and delivers the pulse from a fully charged capacitor each time the gap fires. If properly engineered, synchronous spark gap systems will deliver the largest EMFs to the secondary coil. They are however, the most finicky, and difficult to engineer of any spark gap, and require sophisticated test equipment to set up. Asynchronous gaps are more common. They work quite well and are much easier to run. Fixed or variable speed motors may be used, though variable speed gaps give the builder the most experimental leeway. Break rates need to be in excess of 400 bps, and I have found that breaks rates around 450-480 bps give the best discharge. Since the gap is firing more often than the 60 cycle waveform switches polarity, more power can be fed into the tank circuit, as the capacitors can be charged and discharged more rapidly. Though this system will increase the amount of spark from the secondary, sparks are generally not as long as with synchronous gaps. At higher powers (over 5 kVA) even a rotary gap will not deliver the quench times required for excellent performance unless it is very large. If the arc in the spark gap hangs too long (NOT quenched), it leaves the tank circuit electrically closed. With the gap still firing energy will backflow from the secondary into the primary and create continued oscillation in the tank circuit. The secondary is then suppling energy to maintain the arc in the spark gap. As power levels build, so does the pressure on the spark gap. Engineering more sophisticated gap systems is the only solution in large 1/4 wave coils and Magnifiers. The easiest solution at 5 kVA is to add a static gap in series with the rotary. By messing with the gap settings it is not difficult to develop a gap system that fires smoothly and quenches well. As power levels increase though static gaps will be overwhelmed. More sophisticated gaps are required to replace the static series gaps. Magnetic or airblast gaps must be used in conjunction with the rotary gap to remove the strain on the rotary and get the quench times back down. Somewhere in here I need to cover the Q of spark gaps. Not all spark gaps have the same Q. I have found that using large series static gaps with lots of electrodes; the Q of the gap system decreases as the quench time decreases! Try to avoid static gap designs with more than 6 - 8 electrodes in series. As my power levels went up, and my spark gap Qs went down, I experimented with options to regain performance. I found that by running static gaps in a combination of series/parallel gave me good quench times and I regained some lost Q from the arc having to make so many series jumps. The idea was to split the arc down into two or three equal paths, reducing the current traveling each set of series gaps. In this fashion I was able to achieve excellent quench times with a small rotary running around 5 kVA. The lesson learned was too many gaps in series kills the Q of a spark gap. By adding gaps in parallel, and reducing the number of gaps in series, some Q was regained while power levels increased. This is a valuable hint in spark gap designs. Another factor that should be brought into this discussion is the effects of cooling the electrodes. To start with, I have never run even a simple static gap without some airflow. My first few really good static gaps were constructed inside of PVC pipe sections with a 5" muffin fan on top. The fan did not supply sufficient air to disrupt the arc, but did assist in removing hot ions, and cooling the electrodes down. This allows for longer run times. As my work progressed I realized that reducing the electrode temperature, while not actually quenching the gap, reduces the amount of metal ions introduced into the arc, and makes the gap easier to quench with an airblast or magnets. I am going to cut this off here. I feel I have covered most of the basics, and thrown a few ideas out into the cyberspace. I would be more than happy to expand on spark gap technologies at any time should somebody have any specific questions, comments, problems, or corrections. Remember, armchair debate is no substitute for actually going out an experimenting with a few live systems, and I am always hoping someone will tell me a better way to do it! One final safety note. Spark gaps are loud, and emit a lot of hard UV radiation. Wear hearing protection as required, and never stare at an operating spark gap without welding goggles. To examine the arc on large coils, a sun observation filter on a small telescope will tell you if your gaps are quenching. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 774 Date: 11-16-93 02:40 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ I hope you find some of the information that I posted on spark gaps useful. In the TESLA.ZIP file that I included with the copy of the video tape there are GIF files that I made up showing two of the spark gaps designs that I use, with related text files on each. My airblast gap design on that disk is down and dirty simple, ultra high Q, and gives incredible quench times. If you are running neons up to 4 kVA and want to squeeze every inch of spark out of the coil, this is a gap you might want to look at. The air can be supplied cheaply with an old diaphragm type com- pressor. I have seen reconditioned compressors of this type for around $40-$50 in the surplus catalogs (Surplus Center 1-800-488- 3407). What I did to obtain a long blast to quench the gap was get an old propane tank and install a ball valve in the line to the gap. It takes about 5 min to charge the tank with the diaphragm type compressor, and you get about 90 seconds of quenching. I used a RV trailer type tank, but you can gang them up, or use a larger stationary type tank for longer run times. You will see the same basic gap shown in the video (stripped of the air injection nozzle) as the safety gap for the pole pig. I have two extra electrodes that I machined that are identical to the two shown in the video. If you are interested I will let you have them for $10.00. The material is machine grade brass, and the electrodes weigh 1/4 lb. each, so they sink a lot of heat. Run with the air blast they don't even warm up. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2937 Date: 11-16-93 10:49 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> Thanks for the clarification re: the Schedule 40 pipe - I DH> had always looked at it as being heavier so therefore DH> "better" - never thought of the actual material as being a DH> liability. What about ABS - is there any difference with DH> that? I don't have any experience with ABS plastic secondaries. I have seen some, but had nothing that I could compare to. Look up the RF dissipation factor and that should give you some idea. Off the top of my head, I would GUESS that ABS would work better than PVC; not because I think ABS is any better, but because I know PVC just couldn't be much worse. If I were using ABS I would dry and seal the plastic like PVC. DH> Anyway, we will probably do a couple capacitors in the next DH> week or so. Like I said, I have an OK vacuum pump ( I do DH> graphic arts and printing ) and can pump it out so that DH> should improve things. Good luck on the rolled caps, and look for some different capacitor designs in the next few days. DH> Anyway, many many thanks for your time and help! No problem, glad to be of assistance. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 799 Date: 11-16-93 14:05 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> I was talking with one of the people and they agreed to DH> start on a smaller coil - I was thinking in the order of 4" DH> diameter and about 3' long. The aspect ratio (height to width ratio) is important. The planned coil has an aspect ratio of 9:1 (36" long, 4" diam.) this should be reduced to no more than 5:1 on a 4" diam. coil. 6" coils work best with 4:1 aspect ratio, anything larger 3:1. (cut from another part of a post)* The coil should be wound with good quality magnet wire. I use double Formvar enamel coated magnet wire. Magnet wire gives you maximum inductance. A coil should have over 900 turns, but not too much over 1000 turns. There is a little leeway here. Select a gauge of wire which will allow the aspect ratio and number of turns to fall within this range. ** DH> OK - I made an "editorial decision" today to go for a 6" DH> diameter form and make it 24" long. I just was out running DH> errands and got 1,500' of 22 gauge Heavy Formvar insulated DH> magnet wire so with a diameter of 0.0253, this works out to DH> 948 turns - right in the ballpark that you suggested in DH> another part of this post. Perfect! DH> I think the other people were thinking in the realm of the DH> normal misconception of Tesla coils as being long and skinny DH> but I guess that would make them longer than 1/4 wave… Long skinny coils do not couple well with the primary. What ends up happening is that the primary excites only the bottom half of the secondary, and the top half of the windings are just pushed along by the bottom turns. Long skinny coils get hot at the base, a sign of poor Q. Also they are more subject to splitting and breakdown. By keeping the secondary coil within the given specs, you get a nice low frequency coil, and the field flux from the primary will sweep the entire secondary coil from the bottom turn to the top turn. This way the energy exchange to the secondary is distributed through the entire length of the wire, not just forced into the bottom 300 or so turns. Your decision to go to a slightly larger diam. coil form, and keep the aspect ratio within the specs I recommend, is a good one. Use a large primary coil. BTW 1/4 wave resonate frequency is much more dependant on the length of wire than the dimensions of the coil form. A form that is long & skinny, or short and fat, makes no difference to the 1/4 wavelength of wire. But it makes all of the difference in the world when that wire is intended to be a high Q Tesla coil. Long skinny coils have lower Q, higher corona loss, lower breakdown voltage, and poor coupling coefficients; but will have about the same 1/4 wave frequency as the same length of wire wound on a shorter, fatter coil form. The coil form with aspect ratios and number of turns that fall into the design specs I gave are reliably better performers. DH> OK - I wonder if it would be feasible to make it with DK> continuously variable gap size - something with threaded DK> plastic rods… Experiment away, and get some photos or video if you can. I would be happy to trade tapes or photos even (one for one), and see something new. As much as I do, I never tire of seeing more. DH> I think that since we are starting with neon sign x-formers, DH> we can just use the standard 6" PVC gap you showed - aren't DH> going to be running too much power through it <yet> All of the gaps that I showed, and use, are good ones. The cylinder static gap is a solid performer. I sent along a GIF diagram of this gap showing the internal construction, and a related text file. This project can be built in a few hours with a minimum of shop equipment for around $30.00 if you buy all the parts new. Set the gaps between electrodes at about .035 of an inch, or a little more, for 12 kv neons power supplies. The one disadvantage of this gap is that the electrodes are fixed and cannot be adjusted once bedded in epoxy, but you can jump to any terminal on the gap with ease, changing the number of gaps used in the circuit. Properly constructed, I have gotten 5' discharges from a coil powered with neons using just a single cylinder static gap unit, and the gap electrodes did not melt or pit. Coil forms, regardless of material, should be as thin as possible. Schedule 40 is thick, and is rated for pressure use. Try to locate the thinner "drain" pipe or "flume duct" PVC or other thin wall plastic. If PVC is used, it MUST be dry (baked is preferred) and well sealed with a low loss sealant like poly- urethane or two part epoxy. (RQ previous post) DH> OK - there is some pretty thin wall stuff in our local "Home DH> Center" store - I was worried about mechanical strength DH> though - I can deflect it with little pressure. You'll have to trust me on this one. Handle the secondary with some care, just don't drop or sit on it. <Grin>. If it is built properly with stiff plastic end caps, tightly wound, and well sealed, it will be plenty strong enough to handle casually. Couple of other notes. I have a lathe too. After spending hours setting up wire guides and tensioners, I decided it is much easier and faster to wind coils by hand. The coils turn out better too. It may take a little practice, but it is well worth the time sitting in front of the coil form and laying down the turns by hand, even with thin wire. I can wind a 6" coil in about 45 minutes or less. A first time winder should figure no more than a couple hours. You will spend about the same amount of time figuring out wire guides and tensioners for the lathe set up, and the coil won't be any better quality. DO use the lathe to apply sealer. I set up a couple of heat lamps and a small fan to speed up the dry time, and can get 8 coats down in four hours. By constantly rotating the coil form you get a nice smooth finish that looks and works great! My first "performing" coil was built to nearly the exact specs for the 6" coil you described as being on the drawing board. The coil has held up and still holds a key place in my arsenal. It has survived massive overloads, been used in transmission experiments, as an end resonator on the magnifier, and as a pick up coil to detect RF currents in my house wiring while experimenting with Tesla grounds. You can't hardly go wrong with one, or even two, coils like this. You also mentioned you priced teflon covered wire. This stuff makes killer secondaries, but like you said, "You paid HOW MUCH???". Shop local HAMfests, this wire shows up by the spool at greatly reduced prices in these flea markets. And again, if you have any problems, questions, or need additional advice, feel free to ask. I look forward to hearing about your progress and results. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 800 Date: 11-16-93 14:56 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Last week I posted on recovering and unpotting "dead" neon transformer cores for use in high voltage power supplies. It ocurred to me that those people in warmer parts of the country will not have days cold enough to freeze the tar potting solid enough to chip away cleanly. The tar has to be at least 20 degrees F or colder to chip cleanly and separate away from the warmed core. I hope you thought of the obvious solution if the weather does not cooperate in your area. Put the tar block in the freezer overnight, then proceed with unpotting. Also I tracked down the problem with my system as far as the ASCII characters in the pfc capacitance formula is concerned. My PKZIP is repeatedly stripping out selective ASCII characters when I test it. The divisor of that particular formula is supposed to contain the greek letter pi in it. If you have saved the post, and the formula has the letter pi stripped from the divisor (which I believe is the case) please make a note of it. Without pi in this formula the capacitance given by the equation gets rather large… I sent up a correction, and the problem was repeated. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 912 Date: 11-16-93 15:54 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> Tesla "Q" Factors RQ>Since some people are saving these posts to disk, and at least >one other person (Dave Halliday) is going to embark on some coil >building. I thought I would take a moment and discuss some Tesla >theory that directly relates to coil efficiencies. The subject >is the "Q" factor. Thanks again for the info! >recently gutted. When I inquired, he stated he had to switch to >an ungrounded, wooden, control cabinet because he was drawing >sparks to fingers when he touched the controls… I also recall stories about ham radio shacks having this problem. Used to work for the public aquarium in Boston and we had grounding problems like you wouldn't believe - I was responsible for all of the non-living exhibits ( PA and AV stuff ) and the ground at every single outlet was at a different potential than any other outlet. I once found 50 volts difference between two located 20' apart… A guide was setting up a temporary exhibit and used both outlets for their equipment. They got a bit of a rude awakening that day <grin> TTYL - Dave ë:-) b QMPro 1.51 b Every time I ATDT her, she ATH0's on me… -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 913 Date: 11-16-93 17:08 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> GD> This is geting out of hand, Richard. RQ>Well Guy, I need a place to put all of my stuff where it won't >get rained on. Any other bright ideas? RQ>I have about $5000.00 worth of Tesla equip. ($15,000 replacement >cost), about $5000.00 worth of chemistry equip, not to mention >boxes of homemade pyrotechinics equipment (ball mill, star >presses, rocket ramming table, drying racks, rolls of paper and >tubing, mixing containers, sieves, etc.) I also buy, sell, and >build/rebuild/repair Vespa scooters; own three now, plus parts of >a forth, plus a workbench of special tools for engines, frames, >wheels, etc. RQ>I would like to mess around with some hard vacuum equipment, >and do some bulb blowing/tube bending… and I need a place to >put my shop tools (band saw, drill press, belt sander, table saw, >air compressor, etc.) Geeez Richard - and I thought *I* had too much going on at once what with my boat, woodworking shop, metal shop ( lathe, wirewelder and torches ), music studio, homebrewing, BBS, computers and printing… This takes the cake <grin> b QMPro 1.51 b Tagline Lite: Not funny, but better for you… -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) < CONTINUE HERE - KU > 111983 1438 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 927 Date: 11-19-93 14:38 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Toroid Discharge Terminals Another feature of the "classic" Tesla coil design is the sphere or ball discharge terminal. Tesla clearly was using spheres while he was developing the Colorado Springs oscillator, but during his work there he made the discovery of toroids. Photographs of the Colorado Springs machine clearly shows a brass toroid as part of the antenna mast to prevent corona leakage and premature breakout from the top of the extra coil. As we examine photos of the Wardenclyff machine he built on Long Island, it is clear that the entire tower was constructed to carry the giant toroid terminal. I do not have verifiable infor- mation as to the exact size of this terminal, but it is easily over 50' in diameter. Probably closer to 75-100'. Toroids perform several functions as discharge terminals on Tesla coils. They provide a large top capacitance. This top capacitance helps "cancel" the high inductance in the secondary coil, and increase throughput in the system. They break down at much higher voltages than other shapes. The donut shaped field distributes the charge density. Higher voltages must reached before electrical breakdown occurs. To the coiler this means longer, higher voltage spark. For those of you that have my video, you can see a 30% increase in spark lenghts with no change to input power, the only thing I did was add a larger toroid and retune the system. Toroids sever the coupling. This may be a controversial statement on my part. But from what I have seen, appears to be true. A sphere discharge terminal does not want to separate from the field flux interactions between the primary and secondary. The primary field flux wants to couple the sphere discharger into the system as if it were another turn of the secondary. The spark from the discharger will frequently follow these lines of force, and seek to strike back to the primary. The spark discharge bends back down, and aligns itself with the magnetic lines of force. While this may be useful if you wish to visualize the size and shape of the field, it does nothing to increase your spark lengths. A large toroid on the other hand will establish a field identity that interacts destructively with the primary/secondary field interaction. Since this destructive interaction occurs above the top turns of the secondary is does not affect the coil performance or ability to process energy. It does however allow the spark to leave the system unaffected by the primary/secondary lines of force. This has the effect of allowing a clean getaway for the discharge and promotes those long strikes to the ground or other more distant objects. Toriods also have the beneficial effect of lowering the frequency of the secondary coil dramatically. By loading a large toriod on a relatively small coil, a very low secondary frequency is reached. Low frequency in Tesla systems means long spark. This way a small coil can give big coil performance. Because of this ability of the toriod to drop the frequency of the secondary to such low frequencies, it is important to have a very large primary available that can be tapped out to over 10-12 turns in order to regain the system tune. Larger capacitors may be added, but my experience shows that no additional power or capacitance is required to get big increases in spark production. Clearly the toriod is the ultimate in high Q dischargers and radiators in Tesla systems. Now go out and buy one. I can hear Dave Halliday now….. "You Paid _HOW MUCH?_"!!! Yup, spun aluminum toroids are available commercially, and they run hundreds, even thousands of dollars each. My 20" wide by 5" high commercial toriod ran me over 350 clams. My ten inch secondary needs a toroid at least twice as big to achieve optimum performance, and as commercial toroids get larger, the price increases exponentially. I priced a 40" toroid for my coil at $2000.00 not including shipping, and they gave me a six month deliverly time… So I built one for $35.00, and it works GREAT! I will never spend another penny on commercial spun aluminum toroids. Here are the brief instructions: I buy the 4" or 6" diam. polyproplyene flexible black plastic drain piping. This is made out of ridged plastic, so it does not have a smooth surface, but it easy to bend to form circles of varying diameters. I cut the flange off with a sharp knife, match the ends, and tape them together with wide plastic tape. Once a large ring is formed, I cover the entire surface with wide plastic tape to smooth out the ridges in the material. The goal is to have an even, smooth, surface. The tape choice helps with this con- struction, Mylar and other tapes have no stretch, and are difficult to work with as they wrinkle. I shopped several stores before I found a stretchy material similar to electrical tape. Tape is applied in overlapping strips, or bands, around the drain pipe 4" or 6" cross section. Some surface irregularities are OK. Once the ring is smoothed with a layer of plastic tape, I retape the entire ring with aluminum plumbers tape. This tape comes in two standard widths, I bought a large roll of each. Apply strips of plumbers tape over the prepared surface, make sure the entire surface is covered, and press out any wrinkles with a fingernail or tool. You should now have an aluminized ring. Cut out a circle of thin masonite, wood paneling, or thin plastic so that it will friction fit in the center of the alumunized ring. Place some blocks up under this panel, set the ring in place, and tape the edges all around on both sides with aluminum tape to hold it in place. Spray adhesive and heavy duty foil are used to cover both sides if the center plate. Roll out all wrinkles with a socket or a wood dowel. Works great, about 1/100th the cost. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2 Date: 16 Nov 93 20:33:44 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Well, lets see; I covered basic spark gaps yesterday, next on the list would have to be pulse capacitance. I posted a two part message last month sometime detailing construction of a rolled type pulse discharge capacitor. Since the detail of this partic- ular unit was pretty well covered, I will focus on other homemade types; the flat stacked plate type capacitor, a little on the salt water cap, and a little on capacitor theory as it applies to Tesla coils. I have seen several types of homemade stacked plate capacitors. The two types differ as to the orientation of the plate stacks. Some are stacked vertically, others are stacked horizontally. Before I go into construction details I should cover some of the advantages of flat stacked plate caps for use in Tesla coils and other high voltage applications. Flat plate caps have no inductance. Rolled caps contain two or more plates which are tightly rolled up. Rolled plates exhibit some properties of coils, they contain a certain degree of self inductance. This limits the size of the rolled cap in Tesla applications. As plates grow in size, the self inductance grows, and the caps exhibit self-resonance that will interfere destruct- ively with the oscillation of the Tesla tank circuit. The rolled cap that I posted about previously, is about as large as you can get in a single unit without having self-resonance drop below 1 megahertz. Flat plate caps are better adapted for pulse applications. Rolled caps have to discharge a long plate. The further away the free end of the plate is from the high current terminal, the longer it takes for the cap to discharge. In essence this distance is also an extension of the tank circuit wiring, as the plate gets longer losses increase. Again the rolled capacitor I posted previously is pushing the design limits of efficiency in this area. As the rolled cap gets larger, efficiency of pulsing drops off. Flat plate caps can be constructed to handle higher voltages. Rolled caps have efficiency limits in individual units as to the breakdown voltage. A single dielectric is used per plate. If dielectrics are made thicker, efficiency drops off, if made thinner efficiency increases, but they break down. Using standard materials, the rolled cap I posted about is at the edge of this design limit as well. Flat plate caps can be built for larger capacitance. The rolled cap, because of the design constraints listed above, won't give you much additional capacitance without increases in losses, problems with self-resonance, and lowering of the capacitor Q. The rolled cap that I posted is a good unit. I have built nearly 20 of these caps, and I use them a lot. But do not look to expand much on this design. It has passed through several improvements and I really think it is pushing the design limits in all of the important areas. Next we need to look at the flat plate cap, as there is much to be done yet, but first look at the dielectric. The best Tesla capacitor dielectric is low density polyethylene plastic. Whether you build rolled, stacked plate, or salt water caps you should look hard at this plastic before settling on anything else. It has an extraordinarily low RF dissipation factor for the cost. The actual "in use" dielectric constant on homemade caps using this plastic is right around 2. This is a little lower than the book value, but homemade applications of this dielectric rarely have the close plate bonding that are achieved commercially with clean room vacuum presses. This dielectric melts at 100 deg. C. But because of the very low dissipation factor the plastic is subject to very little in- ductive heating. There is little loss, therefore little heating. When using this plastic however, it is imperative to cover in mineral oil to distribute any heat that is formed, suppress corona and displace air. Plastic caps not covered in oil are guaranteed to fail in seconds. Plates, dielectric, and oil MUST BE CLEAN!… BTW The cheapest and most common plate material is aluminum. In the rolled cap, aluminum flashing is available precut in a perfect plate width, and there are other widths available. Flat plate caps can use flashing, but it is frequently more cost effective to use foil. Now that we have established a few basics, lets talk plate cap design. The first type of flat stacked plate requires the cap be pumped down to a pretty hard vacuum to remove air. This is the horizontal stacked plate capacitor. Typically these are built in a Tupperware type storage box. Plastic, plate, plastic, plate etc. are stacked one atop the other to build up the value. The breakdown voltage is directly related to the dielectric thick- ness used. 60 mil poly sheet is recommended and will have a breakdown voltage in the Tesla tank circuit between 11-17 kv rms input voltage depending on the quality of material, and the cleanliness of the construction. Once the box is filled, and all parallel plate connections are made, high current busses are brought through the lid of the container and sealed airtight with hot glue. Then the lid is snapped on, and it too is sealed with a bead of hot glue around the edges. The next part is important: A single hole is made in the lid for the vacuum connection. A fitting is hot glued into the hole and a hose is attached to the vacuum pump. The cap is pumped down, then the hose is clamped off and disconnected with- out allowing air back into the cap. Submerge the hose in a bucket of clean mineral oil and release the clamp. This allows the oil to backfill the capacitor, and displaces the air that was removed. Once backfilled to normal pressure, I pump them down a second time, and repeat the procedure to make sure that all trapped air between the plates is removed. Air bubbles will form corona hot spots that will cause dielectric failure. The vertical stacked plate capacitor is much like the cap I just covered. But the vertical cap does not require pumpdown. A tank is used to hold the veritcally stacked plates and dielectrics. The unit I examined was built in a glass fishtank that employed no metal in construction. Foam padding was layed in the bottom of the tank, and wedged in around the sides of the vertical capacitor stack to cushion it and wedge it in place. The foam padding also reduced the mineral oil required to cover the stack. The reason these caps do not require pumpdown is that eventually the oil will displace the air trapped in the unit. A break in period of low voltage operation assists the removal of trapped air, as the pulsing of the cap vibrates the plates and agitates the air bubbles. The disadvantage of the unit I examined was the glass fishtank. I have seen plastic waste cans that could be cut down for use as a tank in this construction. Higher Qs, higher voltage, and additional capacitance in stacked plate capacitors can be easily obtained. The trick is to use thinner dielectric. Now the dielectric strength of polyethylene is given as 1000 volts per mil, but this is not the case in Tesla coils. The standard breakdown voltages of a dielectric are calculated using DC voltage. When you run AC across the dielectric, the breakdown voltage must be divided by two. Then you must figure that the peak voltage from a AC sine wave is higher than the rms voltage most people go by. You meter won't see it, but your dielectric will. Then you have resonate rise in the Tesla tank circuit. To give you an idea of resonate rise in a tank, think about the tidal forces that can be created with timed pushes in a bathtub. It don't take much energy to push water over the side. The same principal operates in the tank circuit in a coil, especially with a synchronous gap system. The current pulsing back and forth from capacitor plate to capacitor plate causes a voltage rise that appears on the dielectric in the capacitors. The standard 60 mil poly is supposed to hold up to 60,000 volts per the book. I have blown holes through 60 mil poly with a 12 kv neon sign xfrmr in a Tesla tank circuit and my gap wide open. My pinky finger fit inside the hole. One of the neatest homemade stack plate caps I have seen was built by Bill Richards of T.C.B.O.R., the cost was pretty low, the materials came from his laundry room, the grocery store, and the drugstore. The only thing required was 56 hours of time in arranging the plates according to Bill. But he did end up with .03 uf 15 kv pulse capacitor in a five gallon bucket. It was quite a performer on his coil at 3600 watts! He shopped around for one gallon ziplock freezer bags with a 3 mil thickness. With a sharp scissors he cut the ziplocks off of the tops of the bags. Then he cut aluminum foil squares that fit inside the bag leaving a 1/2" of space around all four sides of the plate. So the plate had dielectric borders 1/2" on all sides. When two bags were stacked on top of one another, there were two layers of dielectric, for a total of 6 mils. Being practical, Bill figured correctly that the stacked bags would hold up to at least 1000 volts rms input in the Tesla tank. He built up stacks that had a value of about .45 uf each, with each stack rated at 1000 volts. Then he wired stacks in series. By squeezing fifteen stacks vertically into a bucket, and covering the whole thing in about three gallons of mineral oil, he got the required capacitance at the required voltage. Since the electrical forces are so well distributed among hundreds of dielectrics, he had plenty of breakdown safety margin. He gave the unit a couple of days to rest after construction, topping it up with oil as required, and gave her the works at 15 kv on a big coil. The heavy buss wiring never even got warm, and even though it bubbled out enough air to displace a few more pints of oil, it did not break down. It turns out that this is a homemade version of commercial pulse discharging capacitors. Stacked capacitor sections of very high value are placed in series until the proper voltage requirement is met. The cap has a very high Q because all of the plates are very close together, with a minimum of connections and bussing required. They deliver a very sharp pulse discharge. Bill's cap was pretty cramped in the bucket. Because of the square shape of the bags, a rectangular tank would have made things easier to fit and wire. But he ran his buss bars through the side of the bucket (sealed with hot glue) and by snapping on the lid, he could pick it up by the handle and move it around with ease. The novice coiler should think about the capacitor requirements and experiment some before beginning large scale homemade caps. Shop for materials; frequently a wholesaler can be found where bulk products (like mineral oil in 5 gallon pails) can be purchased for a fraction of the retail cost. But just because you don't have some big bang pulse caps on line does not mean that you should wait to begin firing a small coil. Nearly every beginner gets hir feet wet in salt water capacitors. Tesla used salt water tanks in Colorado Springs. A tribute to the genius of the man was his ability to develop his huge peak powers using low Q saltwater/glass caps. I do not recommend glass as a dielectric for coiling work. The dielectric constant is much better than plastic, but the RF dissipation factor is so great that they can rupture from dielectric heating (even in salt water the trapped water under the bottles does not circulate) and they always give a spindly, violet colored spark. Polyethylene again is the material of choice, and bottles and buckets can be assembled in a couple of hours that will fire small stuff. I mentioned he before that I have a friend who is firing 5 kVA coils, and still using banks of salt water caps to keep his investment down. As with any homemade capacitor, the salt water must be covered in oil to suppress surface corona. But the quality of oil need not be high, and the capacitors need not be exceptionally clean. A saturated solution of rock salt is all that is needed for the plates. I think I have accomplished what I intended to say on this subject. As always, I am happy to respond on any unclear areas, the need for additional information, or to note corrections. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 864 Date: 11-16-93 20:41 From: Mark Lawton To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>I have about $5000.00 worth of Tesla equip. ($15,000 replacement RQ>cost), about $5000.00 worth of chemistry equip, not to mention RQ>boxes of homemade pyrotechinics equipment (ball mill, star RQ>presses, rocket ramming table, drying racks, rolls of paper and RQ>tubing, mixing containers, sieves, etc.) I also buy, sell, and RQ>build/rebuild/repair Vespa scooters; own three now, plus parts of RQ>a forth, plus a workbench of special tools for engines, frames, RQ>wheels, etc. Sounds just like my stuff! Change the Vespas to dirt bikes and you've got it. I haven't built a coil in a few years, but I'd like to send you a blank VHS to get a copy of your work. Write me back with detailson where to send the tape and the dough. ML, San Diego Fireworks Pyro WinQwk 1.30 #279 -!- WM v3.10/92-0250 ! Origin: Dragnet BBS Oceanside,CA. 619-940-1985 (1:202/401) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 973 Date: 11-17-93 23:52 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>never stare at an operating spark gap without welding goggles. >To examine the arc on large coils, a sun observation filter >on a small telescope will tell you if your gaps are quenching. RQ>… And if all else fails… Put another megavolt through it >_ Blue Wave/QWK v2.12 I got your whole post on Spark Gaps - Once again - Thanks! I had an experience with hard UV light - purchased a small Lincoln Wire Welder and proceeded to ignore the instructions about covering all parts of the body - I was thinking about metal splatters but I never thought about the UV light - wearing sandals at the time and got a bad sunburn on my feet… Status report: Got the wire for the secondary as well as the basic design. I got the 50' of AL flashing for the capacitor as well as all of the PVC pipe and already had the nuts and bolts… Also, found a *wonderful* three terminal plus ground RF filter for 240 volt @ 60 Hz rated at 60 amps! $20 - couldn't resist! I will be able to keep the rest of the electronics in my house ( as well as the neighbors houses ) somewhat happy :) Still looking for a source of the form for the secondary - will be checking prices at local plastics stores when I go to get the 60 mil. Polyethylene sheet - if not, I will use thin-wall PVC but the stuff I saw at a local Home Depot was poorly out of round… Maybe some plexiglass disks glued inside to maintain shape. The local Boeing Aircraft Co. has an interesting "surplus" store that is a little toooo well known but might have something there. Have a bunch of 3/8" refrigeration tubing that I can use for the primary - also into home brewing and this stuff comes in handy… Still need to get the step-up transformer - already have a 12kV 30mA neon but the "potential" transformers you mentioned that were used in power substations sound very good too - will check locally. Pole pig will probably be somewhat later although the demonstration you did on your video - using it - were pretty impressive - the simple Jacobs Ladder was way beyond what a 15kV neon can do - had a really nice sound to it! Anyway - work progresses - I will be busy during this "holiday" season, also the people that were interested in working with me are still very very much interested - showed the primary person your video and their jaw dropped <grin> p.s. - an idea for the gap - you could have a rotary system that also had a valving plate ( circular plate with holes drilled into it ) where the output of the valves could be forced over the spark gaps - pulsed air quenching of a rotary gap - I have a small metal lathe and this might be something to do… As always - Dave b QMPro 1.51 b Klein Bottle for sale - enquire within… -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3090 Date: 11-18-93 00:19 From: Brian Carling To: All Subj: Mega-list parts & kit 1/ ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Names and addresses of companies that supply parts and kits for amateur radio construction: (Updated 17 November, 1993) Here it is folks, the incredible new MEGA-LIST! "624 Kits" No phone listed 171 Springlake Drive Spartanburg, SC 29302 (QRP kits & accessories) A & A Engineering (714) 952-2114 2521 W. La Palma #K Anaheim, CA 92801 Battery charger kits etc. Active Electronics (800) 677-8899 FAX: (514) 697-8112 11 Cummings Park (INT.) (514) 630-7410 Woburn, MA 01801 New electronic parts ADI Co. (800) 233-6261 180 Michael Drive Syosset, NY 11791 Power supplies, batteries etc. Advanced Computer Products Inc. (800) FONE-ACP FAX: (714) 558-8849 1310 E. Edinger (714) 558-8813 Voice Sales Santa Ana, CA 92705 Chips, semiconductors All Electronics (800) 826-5432 (orders) FAX: (818) 781-2653 P.O. Box 567 Voice: (818) 904-0524 INFO Van Nuys, CA 91408 Misc. surplus parts etc. catalog Alltronics (408) 943-9773 2300 Zanker Road San Jose, CA 95131 Components, grab bags etc. Min $15 American Science and Surplus (formerly JerryCo) P.O. Box 48838 Niles IL 60714-0838 ### New address. +1-708-475-8440 +1-708-864-1589 FAX Surplus. *The* surplus place. Lots and lots of surplus. WWII gun cameras, velcro, laser disk chassis, 6 volt VW wipers motors, LEDs, rubber brains, you name it, they've had it. Catalogs are a really good time. $12.50 minimum order (which includes the $4 shipping charge). Amidon Associates (213) 763-5770 12033 Otsego Street North Hollywood, CA 91607 (toroid cores, ferrite beads etc.) Antennas West (800) 926-7373 Box 50062S Provo, UT 84605 Wide variety of antenna kits, loops etc. Antique Audio (512) 467-0304 5555 N. Lamar, Bldg. H-105 Austin, TX 78751 Tubes, parts, books, kits Antique Electronic Supply Co. (602) 820-5411 6221 S. Maple Avenue Tempe, AZ 85283 (Tubes & other components) Antique Radio Classified (508) 371-0512 Write for free sample. P.O. Box 802 Magazine. You'll find almost ANYTHING here Carlisle, MA 01741 for older radios, obscure parts, tubes etc. Appleseed Electronics Inc. (219) 489-9802 P.O. Box 8228 Fort Wayne, IN 46898 Parts ARE Communications Ltd. 44-081-997-4476 6 Royal Parade Hanger Lane, Ealing HF kit for ICOM R-7100 to 200 kHz ! London W5A 1ET & SSB kits for Icom R-100 and R1. Arrow Electronics Inc. (800) 93-ARROW 1860 Smithtown Avenue Catalogs C/O 25 Hub Drive Ronkonkoma, NY 11779 Melville, NY 11747 Minimum $25.00 Components distributor. ARRL 225 Main Stret Newington, CT 06111 (QRP Books, QST Magazine etc.) BCD Electro (214) 343-1770 P.O. Box 830119 Richardson, TX 75083 Catalog, parts, etc. Bigelow Electronics No number listed P.O. Box 125 Bluffton, OH 45817 Parts, Catalog $2. Flyer 1 stamp Brigar Electronics (607) 723-3111 FAX: (607) 723-5202 7-9 Alice Street Binghampton, NY 13904 Parts, gadgets $30 min. C & N Electronics (800) 421-9397 / (612) 429-9397 6104 Egg Lake Road FAX # (612) 429-0292 Hugo, MN 55038 Buy & sell tubes C & S Electronics (203) 866-3208 P.O. Box 2142 Norwalk, CT 06852-2142 Specialty RF chips etc. CeCo Communications (212) 646-6300 2115 Avenue X Brooklyn, NY 11235 (Vacuum tubes) Circuit Board Specialists June 1993 Mailed returned, no forwarding address P.O. Box 969 Pueblo, CO 81002 (Various kits & projects, P.C. boards) Circuit Specialists Inc. (800) 528-1417 Box 3047 Scottsdale, AZ 85271 Electronic components incl. RF parts Circuitwerkes Co. (904) 331-5999 No address FAX: (904) 331-6999 DTMF decoders etc. »> Continued to next message » Message length exceeded, split by WILDMAIL! v3.01 « » Continued in next message « ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3005 Date: 11-18-93 11:45 From: Richard Quick To: Mark Lawton Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ ML> Sounds just like my stuff! Change the Vespas to dirt bikes ML> and you've got it. I haven't built a coil in a few years, ML> but I'd like to send you a blank VHS to get a copy of your ML> work. Write me back with details on where to send the tape ML> and the dough. Richard T. Quick II 10028 Manchester Rd. Suite 253 Glendale, MO 63122 Send a two hour blank VHS high quality tape. $10.00 and a self addressed postage pre-paid mailer. The tape will be return mailed the morning after I get your package. I have sent out three in the last three weeks, so don't worry about me getting rich off this. BTW I will trade video even, tape for tape, for coil, rail gun, high powered laser, and other high voltage stuff. My tapes are one off masters, recorded on SP for highest quality, and a full two hours long. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 867 Date: 11-18-93 15:06 From: Richard Quick To: Joseph Worthington Subj: 10kva Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JW> The thread on the Tesla project is very interesting! JW> If you are the moderator, please let it go on for a while. JW> Joseph Now don't you worry about my friend Guy attempting to snuff my feed. The votes are 100% in my favor, request for the video keep comming in, and even Guy enjoys reading about and thinking up sarcasitc comments (probably jealous with too much time on his hands). Guy gets a little upitty by nature, but he doesn't mean any harm, and if you don't let him get under your skin he can be quite funny at times. And if he does get under your skin, he can take it as well as dish it out. I kind of (almost) look forward to his replies. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3004 Date: 11-18-93 15:22 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Primary coils In order to move towards a complete presentation we need to talk primary coils. This will take me one step closer to coverage of of the major componets in the basic 1/4 wave oscillator. The primary coil is a low resistance, heavy coil, through which the currents produced by the pulse capacitance travel. In discussing primaries we need to cover the "skin effect". Both high voltage and high frequency currents exhibit a property called skin effect. Skin effect describes a situation where the current does not penetrate the conductor, but instead flows on the surface of the conductor. This effect is very pronounced in Tesla tank circuits where both high voltage and high frequency are componets of the capacitor pulse. Studies of the Tesla tank circuit current show that the RF current ringing through the tank has very little penetration of the tank circuit conductors. This should be reflected in the choice of the conductors used to wire the tank circuit, and to wind the primary coil. I have had very good luck with conductors that offer a lot of surface area, as opposed to a large solid cross section. The preferred material for winding primary coils is thin wall soft copper water pipe or refrigerator tubing, wide sheet copper strap, or heavy braided copper ground strap. These matrials offer a low RF impedance, high Q, and large radiating surface areas. For wiring the Tesla tank circuit, such areas as buss connectors to capacitors, tap leads, and spak gap connectors, any of the materials above may be used, but I prefer heavy DC transmission wire. The DC transmission wire (like battery cable or welding cable) offers flexibility and a high grade insulation which helps prevent breakdown. The cables and connections should be carefully examined for areas where Q can be gained. Sharp edges or points should be removed to prevent corona losses, connections should be tight to reduce impedance, and sharp turns should be eliminated to reduce "off axis" inductance. The tank circuit wiring should be as short and straight as possible. The primary coil itself should be wound on a high Q insulator. For a coil form or coil supports, high density poly, plexiglas, lexan, acrylic, or other high Q hard plastic is ideal. The primary coil should be large. I have seen lots of holdovers from the classic age of coil building who insist on 2-3 turn primaries and HUGE capacitors to achieve the proper frequency of operation in the tank circuit. This is wrong. A tank circuit with a small capacitor, and a large primary inductance, will reach down to the same frequencies of operation. A tank circuit of this design will use less power, and therefore require a smaller step up xfrmr. The capacitor will be smaller, which further reduces the cost of the system. A large primary coil offers a much greater surface area for radiation and distributed energy transfer to the secondary. It couples better with a properly designed secondary. Due to these design advantages, an equal or greater amount of power is actually delivered to the secondary, despite the much smaller capacitance and input power. Using a large primary will allow you to reduce the value of your capacitor and your input power by 50% or more (frequently much more) without a reduction in output. Primaries designed to be operated with 9-15 turns will obtain power processing energies that are at least 50% greater than 2-3 turn primaries, provided that the secondaries are constructed to take advantage of the design. Secondary coils with the aspect ratios and numbers of turns that I have recommended here before, work best with large primaries tapped at 9-15 turns. So to give some advice to my friend Dave Halliday, who is building a 6" secondary coil sometime in the near future, plan on winding a primary coil from a conductor material that I have listed above, and use a conductor length of around 75 feet. Your primary should end up about as wide as, or wider, than your secondary is tall. This way the secondary will nest in the large primary. The field flux from the primary will couple the entire length of the secondary winding for a distributed, high efficiency, energy transfer. More energy can be forced into the secondary, with lower input power, and reduced chance of breakdown and loss. Primary coils take several forms depending on the type secondary used with them. Modern secondaries, with high inductance and low aspect ratios, need primaries that are flat pancakes, or "saucer" (rising upwards as the turns move out) shaped spirals. Because this design is so efficient in energy transfers, critical coupling coefficients are achieved without using the old fashion vertical helix type primary coil. When designing primary coils, it is generally a good idea to test a particular coil shape before committing to a time consuming and expensive permanent coil. This is especially true for those who have not had much experience with primary coils of different shapes and sizes. Some cheap low Q wire can be picked up and used to make a temporary primary coil for testing. I set the secondary up on an insulated platform equipped with a good ground, then wind the test primary. To achieve the desired shape I use tire tubes (to build up "saucers") plastic wedges, tape, etc. … If all else fails… Put another megavolt through it. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 869 Date: 11-18-93 21:18 From: Richard Quick To: Dave Tiefenbrunn Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Dave! Got your tape out this morning. Let me know that you got it and what you think of the spark. I was checking the tape for a minute as it was recording… Even I forget sometimes how awesome a 10" secondary looks with a proper discharger and 10 KVA pumped cleanly through it. I think you will agree, get back with me. -!- … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 19 Nov 93 14:38:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Toroid Discharge Terminals Another feature of the "classic" Tesla coil design is the sphere or ball discharge terminal. Tesla clearly was using spheres while he was developing the Colorado Springs oscillator, but during his work there he made the discovery of toroids. Photographs of the Colorado Springs machine clearly shows a brass toroid as part of the antenna mast to prevent corona leakage and premature breakout from the top of the extra coil. As we examine photos of the Wardenclyff machine he built on Long Island, it is clear that the entire tower was constructed to carry the giant toroid terminal. I do not have verifiable infor- mation as to the exact size of this terminal, but it is easily over 50' in diameter. Probably closer to 75-100'. Toroids perform several functions as discharge terminals on Tesla coils. They provide a large top capacitance. This top capacitance helps "cancel" the high inductance in the secondary coil, and increase throughput in the system. They break down at much higher voltages than other shapes. The donut shaped field distributes the charge density. Higher voltages must reached before electrical breakdown occurs. To the coiler this means longer, higher voltage spark. For those of you that have my video, you can see a 30% increase in spark lenghts with no change to input power, the only thing I did was add a larger toroid and retune the system. Toroids sever the coupling. This may be a controversial statement on my part. But from what I have seen, appears to be true. A sphere discharge terminal does not want to separate from the field flux interactions between the primary and secondary. The primary field flux wants to couple the sphere discharger into the system as if it were another turn of the secondary. The spark from the discharger will frequently follow these lines of force, and seek to strike back to the primary. The spark discharge bends back down, and aligns itself with the magnetic lines of force. While this may be useful if you wish to visualize the size and shape of the field, it does nothing to increase your spark lengths. A large toroid on the other hand will establish a field identity that interacts destructively with the primary/secondary field interaction. Since this destructive interaction occurs above the top turns of the secondary is does not affect the coil performance or ability to process energy. It does however allow the spark to leave the system unaffected by the primary/secondary lines of force. This has the effect of allowing a clean getaway for the discharge and promotes those long strikes to the ground or other more distant objects. Toriods also have the beneficial effect of lowering the frequency of the secondary coil dramatically. By loading a large toriod on a relatively small coil, a very low secondary frequency is reached. Low frequency in Tesla systems means long spark. This way a small coil can give big coil performance. Because of this ability of the toriod to drop the frequency of the secondary to such low frequencies, it is important to have a very large primary available that can be tapped out to over 10-12 turns in order to regain the system tune. Larger capacitors may be added, but my experience shows that no additional power or capacitance is required to get big increases in spark production. Clearly the toriod is the ultimate in high Q dischargers and radiators in Tesla systems. Now go out and buy one. I can hear Dave Halliday now….. "You Paid _HOW MUCH?_"!!! Yup, spun aluminum toroids are available commercially, and they run hundreds, even thousands of dollars each. My 20" wide by 5" high commercial toriod ran me over 350 clams. My ten inch secondary needs a toroid at least twice as big to achieve optimum performance, and as commercial toroids get larger, the price increases exponentially. I priced a 40" toroid for my coil at $2000.00 not including shipping, and they gave me a six month deliverly time… So I built one for $35.00, and it works GREAT! I will never spend another penny on commercial spun aluminum toroids. Here are the brief instructions: I buy the 4" or 6" diam. polyproplyene flexible black plastic drain piping. This is made out of ridged plastic, so it does not have a smooth surface, but it easy to bend to form circles of varying diameters. I cut the flange off with a sharp knife, match the ends, and tape them together with wide plastic tape. Once a large ring is formed, I cover the entire surface with wide plastic tape to smooth out the ridges in the material. The goal is to have an even, smooth, surface. The tape choice helps with this con- struction, Mylar and other tapes have no stretch, and are difficult to work with as they wrinkle. I shopped several stores before I found a stretchy material similar to electrical tape. Tape is applied in overlapping strips, or bands, around the drain pipe 4" or 6" cross section. Some surface irregularities are OK. Once the ring is smoothed with a layer of plastic tape, I retape the entire ring with aluminum plumbers tape. This tape comes in two standard widths, I bought a large roll of each. Apply strips of plumbers tape over the prepared surface, make sure the entire surface is covered, and press out any wrinkles with a fingernail or tool. You should now have an aluminized ring. Cut out a circle of thin masonite, wood paneling, or thin plastic so that it will friction fit in the center of the alumunized ring. Place some blocks up under this panel, set the ring in place, and tape the edges all around on both sides with aluminum tape to hold it in place. Spray adhesive and heavy duty foil are used to cover both sides if the center plate. Roll out all wrinkles with a socket or a wood dowel. Works great, about 1/100th the cost. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3066 Date: 11-19-93 14:38 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Toroid Discharge Terminals Another feature of the "classic" Tesla coil design is the sphere or ball discharge terminal. Tesla clearly was using spheres while he was developing the Colorado Springs oscillator, but during his work there he made the discovery of toroids. Photographs of the Colorado Springs machine clearly shows a brass toroid as part of the antenna mast to prevent corona leakage and premature breakout from the top of the extra coil. As we examine photos of the Wardenclyff machine he built on Long Island, it is clear that the entire tower was constructed to carry the giant toroid terminal. I do not have verifiable infor- mation as to the exact size of this terminal, but it is easily over 50' in diameter. Probably closer to 75-100'. Toroids perform several functions as discharge terminals on Tesla coils. They provide a large top capacitance. This top capacitance helps "cancel" the high inductance in the secondary coil, and increase throughput in the system. They break down at much higher voltages than other shapes. The donut shaped field distributes the charge density. Higher voltages must reached before electrical breakdown occurs. To the coiler this means longer, higher voltage spark. For those of you that have my video, you can see a 30% increase in spark lenghts with no change to input power, the only thing I did was add a larger toroid and retune the system. Toroids sever the coupling. This may be a controversial statement on my part. But from what I have seen, appears to be true. A sphere discharge terminal does not want to separate from the field flux interactions between the primary and secondary. The primary field flux wants to couple the sphere discharger into the system as if it were another turn of the secondary. The spark from the discharger will frequently follow these lines of force, and seek to strike back to the primary. The spark discharge bends back down, and aligns itself with the magnetic lines of force. While this may be useful if you wish to visualize the size and shape of the field, it does nothing to increase your spark lengths. A large toroid on the other hand will establish a field identity that interacts destructively with the primary/secondary field interaction. Since this destructive interaction occurs above the top turns of the secondary is does not affect the coil performance or ability to process energy. It does however allow the spark to leave the system unaffected by the primary/secondary lines of force. This has the effect of allowing a clean getaway for the discharge and promotes those long strikes to the ground or other more distant objects. Toriods also have the beneficial effect of lowering the frequency of the secondary coil dramatically. By loading a large toriod on a relatively small coil, a very low secondary frequency is reached. Low frequency in Tesla systems means long spark. This way a small coil can give big coil performance. Because of this ability of the toriod to drop the frequency of the secondary to such low frequencies, it is important to have a very large primary available that can be tapped out to over 10-12 turns in order to regain the system tune. Larger capacitors may be added, but my experience shows that no additional power or capacitance is required to get big increases in spark production. Clearly the toriod is the ultimate in high Q dischargers and radiators in Tesla systems. Now go out and buy one. I can hear Dave Halliday now….. "You Paid _HOW MUCH?_"!!! Yup, spun aluminum toroids are available commercially, and they run hundreds, even thousands of dollars each. My 20" wide by 5" high commercial toriod ran me over 350 clams. My ten inch secondary needs a toroid at least twice as big to achieve optimum performance, and as commercial toroids get larger, the price increases exponentially. I priced a 40" toroid for my coil at $2000.00 not including shipping, and they gave me a six month deliverly time… So I built one for $35.00, and it works GREAT! I will never spend another penny on commercial spun aluminum toroids. Here are the brief instructions: I buy the 4" or 6" diam. polyproplyene flexible black plastic drain piping. This is made out of ridged plastic, so it does not have a smooth surface, but it easy to bend to form circles of varying diameters. I cut the flange off with a sharp knife, match the ends, and tape them together with wide plastic tape. Once a large ring is formed, I cover the entire surface with wide plastic tape to smooth out the ridges in the material. The goal is to have an even, smooth, surface. The tape choice helps with this con- struction, Mylar and other tapes have no stretch, and are difficult to work with as they wrinkle. I shopped several stores before I found a stretchy material similar to electrical tape. Tape is applied in overlapping strips, or bands, around the drain pipe 4" or 6" cross section. Some surface irregularities are OK. Once the ring is smoothed with a layer of plastic tape, I retape the entire ring with aluminum plumbers tape. This tape comes in two standard widths, I bought a large roll of each. Apply strips of plumbers tape over the prepared surface, make sure the entire surface is covered, and press out any wrinkles with a fingernail or tool. You should now have an aluminized ring. Cut out a circle of thin masonite, wood paneling, or thin plastic so that it will friction fit in the center of the alumunized ring. Place some blocks up under this panel, set the ring in place, and tape the edges all around on both sides with aluminum tape to hold it in place. Spray adhesive and heavy duty foil are used to cover both sides if the center plate. Roll out all wrinkles with a socket or a wood dowel. Works great, about 1/100th the cost. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 928 Date: 11-19-93 16:31 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> Geeez Richard - and I thought *I* had too much going on at DH> once what with my boat, woodworking shop, metal shop ( DH> lathe, wirewelder and torches ), music studio, homebrewing, DH> BBS, computers and printing… DH> This takes the cake <grin> Isn't it funny how intelligence and imagination breeds havoc? Mark Lawton (spel) sent me a post about all of his concurrent projects too. It seems we landed in a nice spot to exchange a few ideas and interests. This conference is not too crowded, yet several people end up with similar sets of hobbies and interests. BTW to keep somewhat on topic, I really hope your coiling efforts are moving along. I have tried to dump as much as possible in the last few days, and have spent several hours per day in organizing my thoughts and getting them out. Between the video tape and the posts you should have sufficient information to be able to build a really hot coil system or two. I wish you the best of luck, and if you need any clarification, further explaination, or any such, drop me a post. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 929 Date: 11-19-93 16:49 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ >recently gutted. When I inquired, he stated he had to switch to >an ungrounded, wooden, control cabinet because he was drawing >sparks to fingers when he touched the controls… DH> I also recall stories about ham radio shacks having this DH> problem. DH> Used to work for the public aquarium in Boston and we had DH> grounding problems like you wouldn't believe - I was DH> responsible for all of the non-living exhibits ( PA and AV DH> stuff ) and the ground at every single outlet was at a DH> different potential than any other outlet. I once found 50 DH> volts difference between two located 20' apart… A guide DH> was setting up a temporary exhibit and used both outlets for DH> their equipment. They got a bit of a rude awakening that DH> day <grin> A few months back when our local sysop first added this conference, there was an thread on grounds and grounding that you just would not believe (well maybe you would), anyway, the misunderstandings and misconceptions about grounds and grounding, and the bizzare things that happen when equipment and systems are not properly grounded… I have threatened to write a book on the subject and post it chapter by chapter! Tesla was the first person to apply ground to a tuned circuit. His studies of grounds, and grounding practices was extremely extensive, but unfortunately little was documented or survived. By reading the Colorado Springs Notes it is quite clear that Tesla struggled to get a good ground on site for his system and cited the local geology (sand & rock) as the source of his problem. He eventually had to run water 24 hours a day over his ground. He used a two ground system in his CS lab, and documents the resistance, and electrical distance between the two. The system ground was a 3' square copper plate dropped in the bottom of a 12' hole with a couple of wheelbarrows of coke dumped on top. The hole was backfilled and watered as I mentioned. His control, or line frequency, ground was the water pipe. Tesla was capable of producing serious ground currents from the machine. Some of the effects were reported many miles away; sparks comming off the the shoes of horses which caused the animals to spook, clouds of insects covered in St.Elmos fire, in addition to the locals getting sparks from their water taps. When he went on to Wardenclyff, he spent half of the tower construction cost on the well with 18" copper plated steel pipe driven into bedrock 50' below the water table. He did not intend to mess around. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 111993 1704 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 930 Date: 11-19-93 17:04 From: Richard Quick To: David Tiefenbrunn Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DT> I have sent you a video tape. I hope the DT> offer is still good. I included a few DT> minutes of the first run of the 45KW generator. DT> The new lab sounds great. DT> Of course, you will probably get the tape before DT> this message. :) Yeah I did! And you will probably get the tape back before you get this message. It went out yesterday. Yes the offer is still good, and so is the tape. You will really enjoy watching it. New lab so far is looking good. Expensive, contractor wants $32.50 per square foot. Read my letter in with the tape about the generator video. I am still kicking myself (I recorded over it before I read your letter) BTW I will trade tapes happily if anyone has goodies I would be interested in. Video tape is an excellent way to archive our little projects; not only are they useful as a personal reference, but they are amazingly effective teaching tools. Nothing explains something like a coil project as well as the designer/operator pointing to, and talking about, the operational working equipment. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 930 Date: 11-19-93 17:04 From: Richard Quick To: David Tiefenbrunn Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DT> I have sent you a video tape. I hope the DT> offer is still good. I included a few DT> minutes of the first run of the 45KW generator. DT> The new lab sounds great. DT> Of course, you will probably get the tape before DT> this message. :) Yeah I did! And you will probably get the tape back before you get this message. It went out yesterday. Yes the offer is still good, and so is the tape. You will really enjoy watching it. New lab so far is looking good. Expensive, contractor wants $32.50 per square foot. Read my letter in with the tape about the generator video. I am still kicking myself (I recorded over it before I read your letter) BTW I will trade tapes happily if anyone has goodies I would be interested in. Video tape is an excellent way to archive our little projects; not only are they useful as a personal reference, but they are amazingly effective teaching tools. Nothing explains something like a coil project as well as the designer/operator pointing to, and talking about, the operational working equipment. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 931 Date: 11-20-93 00:42 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Tesla Coil Builders Association I posted this address a few months back, but many people dropped in recently so I will post it back up again. The organization is called TCBA for short and is run by one, Harry Goldman, retired high school science teacher. He publishes a quarterly news letter called _NEWS_ The news letter has articles submitted by members on a regular basis, new coil designs, sparks gaps (my first submission was published here), spark photos, articles on "classic" coils gleened from age old science magazines, questions and answers sections, as well as a "trading post" buy and sell section for new and used HV caps, xfrmrs, coils, coil forms, etc., and a list of the best commercial parts suppliers. Subscriptions and membership is $24.00 U.S., $30 CAN., and includes a framable certificate. Harry has been publishing the NEWS since 1982 and all back issues are available as well a a comprehensive index of all articles in those back issues. If you are interested write to: Harry Goldman TCBA 3 Amy Lane Queensbury, NY 12804 Tel: (518) 792-1003 Tell him I sent you!!! -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1339 Date: 11-20-93 18:24 From: Joseph Freivald To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ For those of us who are wanna bees, What's a tesla coil, and why does it get at least 10 posts per day? Just trying to catch up, Joe ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1040 Date: 11-21-93 22:40 From: David Tiefenbrunn To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ On 11-18-93 Richard Quick wrote to Dave Tiefenbrunn… RQ> Got your tape out this morning. Let me know that you got it and Tape recieved 11-20-93. As was the post quoted herein. RQ> what you think of the spark. I was checking the tape for a minute RQ> as it was recording… Even I forget sometimes how awesome a 10" RQ> secondary looks with a proper discharger and 10 KVA pumped RQ> cleanly through it. I think you will agree, get back with me. *Quite* awsome… Previously the largest Tesla coil I had seen was in a science museum in Boston, MA. It's spark was maybe 1/2 of the >small< coil in your video. I *used* to think it was a big one. At what power level does it become dangerous to draw spark with the pole? The one I built when I was in college (over 10 years ago) had 230W input, but I didn't have all the details of how to optimize / tune it. It still threw sparks a few inches long. It also had a nasty static charge that would build up while it was running, and while I drew sparks (with a rod) the static charge would pop and I'd get a jolt. Your coils never displayed that particular problem in the video, just nice clean HV RF. I'm going to show a few friends your tape. One of them has a small (by your standards) coil. His coil's primary is wound like a regular coil, not flat like yours (or for that matter, the others I've seen. I will have to check with him to find out why. I think he is useing flat glass / foil caps. With a little luck & timing maybe I can get video of it when we do the generator tape deal. (see other post) I have been saving all of the "how to" stuff for future reference. TTYL, Dave _ * OFFLINE 1.54 * I love the smell of ozone in the morning. -!- Maximus 2.01wb ! Origin: =Abbey Road BBS= Higganum, Ct. (203)345-7635 (1:320/5967) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1102 Date: 11-21-93 23:01 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> Primary coils RQ>In order to move towards a complete presentation we need to >talk primary coils. This will take me one step closer to >coverage of of the major componets in the basic 1/4 wave >oscillator. Once again - THANKS! Also, just had a bit of a "conceptual" breakthrough - was trying to see why 1/4 wave was best and then saw that this is 1/4 wave reflected over a ground plane… Makes a lot of sense ( arcs too ) Again, this has been saved, will be printed tomorrow. ::Status report:: Got some PVC pipe - flimsy stuff but I will use wooden braces to hold it circular while I wind it. Actually, will probably cut out some plexi circles and glue them in… Got a bunch from some old signs Still have yet to get to the plastics store to get the material for the capacitors but looking at this week - also probably "have" to make a run to one of our distributors located near the Boeing surplus store - check for teflon wire as well as "exotic" 6" tubes… Question - there are some very cheap cutting boards available made out of a high-density polyethylene plastic - was thinking of using them for the "breadboard" for the transformer protection stuff as well as the base of the coil - do you have any feedback on the Q of this material Thank you for your post on Primary coils - haven't read it completely but I got the idea that the diameter was critical - will check and get large tubing if that is true… Again - TTYL - Dave ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3181 Date: 11-21-93 23:11 From: David Tiefenbrunn To: Richard Quick Subj: 45KVA generator ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Hello, Richard. I know what you mean about the "wonderful" day. Send me a tape. I have approximatly 30 minutes of cranking the generator for the first run. Obviously, being the first attempt, I had no idea how long or what it would take to get it running. After working the crankshaft back & forth by "hand", and getting the starters to turn the thing over, I found it had no compresion. So I took the head off, and did a valve job. 2 new valves, and 5 springs. Almost needed seats but there was enough left of them. I will edit that down to a reasonable length, depending on the length of the tape you send. I can also do a "tour" of the unit, if you like. And, for that matter, some of the other somewhat less than common stuff / equiptment I have collected or constructed. I have some shots of the internal parts of the engine, as after getting it started, I discovered it needed an oil ring on cylinder #1. I use an S-VHS camcorder, and make dubs to VHS HI-FI. The sharpness of the picture w/S-VHS is a huge improvement over VHS. It is very close to laser disc quality, so the dubs come out as good as an original (not a copy) VHS tape would be. I will let my sysop know about the double echos, and that I apparently have been loosing replys. I am beginning to think about setting up my own BBS, also. Post a message about what to tape, and or send your blank, and I will get it back ASAP. TTYL, Dave * OFFLINE 1.54 * I love the smell of ozone in the morning. Origin: =Abbey Road BBS= Higganum, Ct. (203)345-7635 (1:320/5967) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1008 Date: 11-22-93 03:18 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> Status report: DH> Got the wire for the secondary as well as the basic design. OK, I got some soft figures for you. Given the specs of the planned coil you gave me here's what your looking at: Bare secondary frequency around ~260 kHz Secondary top loaded with 18" diam, 4" cross section toriod will resonate around ~180 kHz Using the rolled capacitor as per my specs you should get .02 uf capacitance, so to tune this secondary in on the tank circuit, your tank will have to be: Saucer shaped sprial wound primary. Angle of inclination from first turn to last turn will be right around 30 degrees slope; this should give pretty close to critcal coupling with this secondary. Diameter of the first turn (inside diameter) will need to be ~9" giving you 1-1/2" space between the coils. With the toroid discharge terminal on the secondary coil, the tank should tune in when the primary is tapped right around 9 turns. These numbers are going to off a little, but I tuned a guys coil once over the telephone when he was six states away. I was throwing stuff off the top of my head and set the coil up in my mind from his verbal description. He claimed I had the coil in it's best tune the first time he turned it on, said every time he altered anything the spark decreased. It COULD have been dumb luck… But I checked the numbers you gave me against my programs and my documented systems in this size. You'll need at least 9 turns on a saucer primary to get that coil to fire with that cap. DH> I got the 50' of AL flashing for the capacitor as well as DH> all of the PVC pipe and already had the nuts and bolts… Your looking good here. DH> Also, found a *wonderful* three terminal plus ground RF DH> filter for 240 volt @ 60 Hz rated at 60 amps! $20 - DH> couldn't resist! I would have picked it up too. This is looking good, be sure to run the filter backwards. If your using only one filter, place it between in the supply line before the variac. Ground the case to your 60 cycle neutral. DH> Still looking for a source of the form for the secondary - DH> the stuff I saw at a local Home Depot was poorly out of DH> round… DH> Maybe some plexiglass disks glued inside to maintain shape. I would avoid using baffels inside the coil form, they tend to reduce the Q of the coil. Find a different supplier for some rounder pipe before you go this route. DH> Have a bunch of 3/8" refrigeration tubing that I can use for DH> the primary - Just fine for this sized primary coil, make sure it is long enough, though you can braze in a splice for added length. DH> Still need to get the step-up transformer - already have a DH> 12kV 30mA neon but the "potential" transformers you DH> mentioned that were used in power substations sound very DH> good too - will check locally. If you use 12 kv neons you will need about 120 ma total to drive this coil to good spark. That's four 12,30s. DH> Pole pig will probably be somewhat later although the DH> demonstration you did on your video - using it - were DH> pretty impressive - the simple Jacobs Ladder was way beyond DH> what a 15kV neon can do - had a really nice sound to it! I should hope so!!! I run the Jacobs Ladder between 5-7 kVA with a rail voltage of 20,000 volts. DH> Anyway - work progresses - I will be busy during this DH> "holiday" season, also the people that were interested in DH> working with me are still very very much interested - showed DH> the primary person your video and their jaw dropped <grin> His was not the first, and won't be the last!!! You should have seen the look on MY face while I was running it! I was 20' away and under cover and the sparks looked like they were going to wipe my nose for me. DH> p.s. - an idea for the gap - you could have a rotary system DH> that also had a valving plate ( circular plate with holes DH> drilled into it ) where the output of the valves could be DH> forced over the spark gaps - pulsed air quenching of a DH> rotary gap - I have a small metal lathe and this might be DH> something to do… I think I understand the idea, may be a good one. I can give you specs for basic systems that will give excellent performance. But for ideas like this, I encourage people to develop as far as profitable. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1034 Date: 11-22-93 18:53 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Tuning The Tesla Tank Circuit Once a Tesla coil is set up and ready to fire, certain steps should be taken before power is applied. Don't expect to throw the works on a newly built or newly re-arranged system. If you do you may have to go back to the drawing board. The coil must be brought into tune, and up to power gradually. The use of a variac autotransformer is highly recommended for controlling power on a system, even if the coil is eventually to be used in on/off applications. Never throw full power to a coil until you are sure the system is in proper tune. Set the tank circuit up first. Double check all of your connections. Run your grounds and double check those, never take a solid connection for granted. Set the secondary into the primary and ground it. Use a small discharge terminal at first if available. The smaller terminal will break down and produce spark at a lower voltage than a larger terminal, and new setups are not the place to stress the secondary. CLOSE YOUR SPARK GAPS DOWN! This is the numero uno step in bringing a coil into tune, don't run a lot of gap. I set up a static test with the power supply and no capacitors. Close down the safety gap until it has reached the point where the transformer will jump the gap 50% of the time when full voltage is applied in the test. Measure this gap distance and record it. When tuning a coil you will reduce this safety gap distance by 50% to provide kickback protection. It is a good idea to run a static test on the main system spark gap and close it down by 75% But on some gap systems this may not be practical, as series gaps behave much differently that a single gap. These differences are caused by the opposing lines of force in the single gap used for the safety. Apply a bit of power until the tank circuit fires. If no spark breakout is seen from the discharge terminal don't worry. Use a florescent bulb as an indicator. As the coil is closer to tune, the farther and brighter the bulb will glow. Turn off the coil and move the tap connection on the primary coil a half turn and check the bulb brightness, then move it a full turn in the opposite direction and note the brightness of the bulb again. This way you can determine the direction the tap needs to be moved to locate the tune spot. Open the main and safety gaps up in steps. Apply the same voltage input (low power) and check for discharge. Once spark has begun to break out of the discharge terminal use it as a visual indicator of tune as long as full power is not applied. With full power into a system the spark frequently gets so wild and distracting you cannot judge accurately. I have found that recording the tuning on video, and watching the tape provides a way to look at the system objectively. A system in proper tune should not break down the safety gap. The safety gap set at the full static test setting should not be too acitive. Once the coil is in good tune the safety gap electrodes may be opened to the point where the gap only fires perhaps once every three or four seconds weakly. Tuning is an art, and it takes a little practice. I recently came across some information that will be quite helpful for the novice (and even an expert on high powered systems) obtain better tuning. Use an arc meter. The arc meter is made by suspending a series of gaps on monofiliment fishing line. One end of the arc meter is connected to the toroid, the other end of the meter is strung across the room and grounded. By placing a series of air gaps on an insulated line, the arc strength and voltage may be accurately gaged with the eye. Discharge will follow the gap path (it looks like a ray gun firing) and gaps may be counted as a reference. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1333 Date: 11-23-93 10:28 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> Geeez Richard - and I thought *I* had too much going on > DH> at once what with my boat, woodworking shop, metal shop ( > DH> lathe, wirewelder and torches ), music studio, > DH> homebrewing, BBS, computers and printing… RQ> DH> This takes the cake <grin> RQ>Isn't it funny how intelligence and imagination breeds havoc? Havoc… Now *that's* a polite term for it <grin> RQ>Mark Lawton (spel) sent me a post about all of his concurrent >projects too. It seems we landed in a nice spot to exchange a >few ideas and interests. This conference is not too crowded, >yet several people end up with similar sets of hobbies and >interests. Great! I am looking to connect to a local source for FIDO just for this conference… RQ>BTW to keep somewhat on topic, I really hope your coiling >efforts are moving along. I have tried to dump as much as >possible in the last few days, and have spent several hours >per day in organizing my thoughts and getting them out. I sent you a status report a couple days ago - just getting stuff together right now. I will be going to the Boeing surplus place today and will see if they have anything of interest - they are closed on Monday - they put all the new stuff out then so Tuesday is the primo day to go there… TTYL - Dave ë:-) ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1334 Date: 11-23-93 10:36 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> Used to work for the public aquarium in Boston and we had > DH> grounding problems like you wouldn't believe - I was RQ>A few months back when our local sysop first added this >conference, there was an thread on grounds and grounding that >you just would not believe (well maybe you would), anyway, the >misunderstandings and misconceptions about grounds and >grounding, and the bizzare things that happen when equipment >and systems are not properly grounded… I can well imagine - I also did PA systems for bands for a while and some of the perceptions about power and signal grounds were amazing. Not so much for their blind ignorance and lack of common sense but for the fact that some of them were still alive <grin> RQ>By reading the Colorado Springs Notes it is quite clear that >Tesla struggled to get a good ground on site for his system >and cited the local geology (sand & rock) as the source of his >problem. He eventually had to run water 24 hours a day over >his ground. Interesting - the water table there is probably pretty low so that would be a problem. In Seattle, the reverse is true - where I live is fairly close to Lake Washington and the ground is pretty wet all year round. I will probably drive a couple lengths of coper pipe into the earth for the coil ground - the ground for the house is a 6' copper rod but from what you say, the more the merrier! RQ>His control, or line frequency, ground was the water pipe. >Teslawas capable of producing serious ground currents from the >machine. Some of the effects were reported many miles away; >sparks comming off the the shoes of horses which caused the >animals to spook, clouds of insects covered in St.Elmos fire, >in addition to the locals getting sparks from their water >taps. Must have been fun to live near there <grin> RQ>When he went on to Wardenclyff, he spent half of the tower >construction cost on the well with 18" copper plated steel >pipe driven into bedrock 50' below the water table. He did not >intend to mess around. Jeeezzz! I guess not!!! That is getting a bit serious! ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1335 Date: 11-23-93 10:38 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> Harry Goldman > TCBA > 3 Amy Lane > Queensbury, NY 12804 > Tel: (518) 792-1003 RQ>Tell him I sent you!!! Thanks! Will do ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1337 Date: 11-23-93 11:16 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> Primary coils Me again… This is exactly the info I need! I was wondering what would work best. >primary coil should be large. I have seen lots of holdovers >from the classic age of coil building who insist on 2-3 turn >primaries and HUGE capacitors to achieve the proper frequency >of operation in the tank circuit. RQ>This is wrong. RQ>A tank circuit with a small capacitor, and a large primary >inductance, will reach down to the same frequencies of >operation. A tank circuit of this design will use less power, >and therefore require a smaller step up xfrmr. The capacitor >will be smaller, which further reduces the cost of the system. Makes a lot of sense! Also, because of the losses in the capacitor, using a lower value will result in less loss… RQ>So to give some advice to my friend Dave Halliday, who is >building a 6" secondary coil sometime in the near future, >plan on winding a primary coil from a conductor material that >I have listed above, and use a conductor length of around 75 >feet. Your primary should end up about as wide as, or wider, >than your secondary is tall. Got it! I was thinking of using some 3/8ths refrigeration tubing but since the surface area is important, I'll probably get a reel of 3/4ths or 1/2" tubing ( gotta check on pricing first ) Also, I wasn't thinking about the length of the primary and I only have about 20' of the small tubing. I'll be going to Boeing today so they might have something there too. Again - many thanks for the info - I have a pretty good handle on what is needed - like I said, probably building the capacitor over the Thanksgiving weekend - I'll be closing the store then… Trade some videos / photos once I get something to show. b QMPro 1.51 b Neurotoxin Lite! Tastes great… Less drooling… ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3185 Date: 11-23-93 15:21 From: Richard Quick To: David Tiefenbrunn Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DT> Tape recieved 11-20-93. As was the post quoted herein. RQ> what you think of the spark. I was checking the tape for a RQ> minute as it was recording… Even I forget sometimes how RQ> awesome a 10" secondary looks with a proper discharger and RQ> 10 KVA pumped cleanly through it. I think you will agree, DT> *Quite* awesome… Previously the largest Tesla coil DT> I had seen was in a science museum in Boston, MA. DT> It's spark was maybe 1/2 of the >small< coil in your DT> video. I *used* to think it was a big one. Yup, we have one in our science muesum too. Small system putting out about 2' of spark. I decided I could do a little better if I put my mind to it. DT> At what power level does it become dangerous to DT> draw spark with the pole? This is a very good question. Very good. I routinely pull spark off of my coils with a key, pipe, or other conductor. It is not the power level of the spark that makes a difference, it is the quality of insulation you are standing on and the distance you place yourself from ground. I have had sparks coming off of my shoes over a foot long while in direct contact with voltages of at least a million volts. I can light 40 watt bulbs from the CURRENT heating the filament, and my body in series with the circuit. Power arcs leaving the body and hitting the ground are very dangerious, especially for those who are more shock sensitive than myself. I do not experience "shocks" in these instances, but do feel the RF burns. I have also had a few RF burns from change, keys, etc. on my person, as well as having lost all the magnetic strips on my bank and credit cards. My brother lost a nice digital watch once. But, if you know what you are doing, and the system is well set up in proper tune, it is OK to take up to 5 kVA output through a conductor to your person. But this is not recommended for amateurs. There IS a danger with certain tank circuits. I never ground the tank circuit or the primary coil, nor do I connect the secondary anywhere to the tank circuit or the primary. Coils with the primary and secondary connected, or both grounded to system ground can be LETHAL!!!! This allows an open pathway for deadly 60 cycle from the step up xformer to appear in the spark discharge. I avoid this problem by never using these circuits. My tank circuits and primary coils float ungrounded. Remember tank circuits are always deadly. A person with a conductor in hir hand and approaching a Tesla coil had better know the circuit, and have a cool head. Accidental contact with a primary coil or tank circuit has thought provoking possibilities. Like I stated in my original post when offering video: I cannot be responsible for people attempting to reproduce any of the experiments that I perform on the tape. I know what I am doing. DT> The one I built when I was in college (over 10 years DT> ago) had 230W input, but I didn't have all the details DT> of how to optimize / tune it. You do now! DT> It still threw sparks a few inches long. It also had a DT> nasty static charge that would build up while it was DT> running, and while I drew sparks (with a rod) the static DT> charge would pop and I'd get a jolt. Your coils never DT> displayed that particular problem in the video, just nice DT> clean HV RF. Yup, they do run clean. Very little RFI, high output, and efficient. Even my little temporary test setups perform better than most peoples end product. Having seen a lot of coils, and talking with people that build them, I feel qualified to post to "ALL". Nobody here has said any different. I know the circuits and systems to the point where I literally dream about them sometimes. I have set up and fired systems in my dreams several times, and I find the data I get from there is as valid as anything I do while awake. DT> I'm going to show a few friends your tape. Please do. All I ask is that you do not make copies without my permission. DT> One of them has a small (by your standards) coil. His DT> coil's primary is wound like a regular coil, not flat like DT> yours (or for that matter, the others I've seen. I will have DT> to check with him to find out why. Most likely his plan or design hails back to the "classic" era of coil building where a vertical helix primnary (all primary turns equally spaced from the secondary) was common. This type primary is used to couple energy into systems using the "classic" style, space wound or low inductance secondary coil. The design I promote has been completely modernized and takes full advantage of modern high Q construction materials. The very high inductance secondary is so much more efficient that you have to reduce the aspect ratio of the primary coil or it will force a breakdown of the secondary from overloading. Then I use toroids to balance the secondary right to the load limit. The result of this work on my 10" coil has yielded sparks to the strike rail protecting the primary that are as fat as my leg, and up to 15' full current strikes. The spark is fully five times the length of the secondary winding which is only 32" high. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1340 Date: 11-23-93 17:49 From: Dave Halliday To: Joseph Freivald Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JF>For those of us who are wanna bees, What's a tesla coil, and >why does it get at least 10 posts per day? JF> Just trying to catch up, > Joe Hi Joe - the Tesla coil is basically a high-frequency resonant air transformer - oscillator system. It was developed by a wonderful genius / wildman Nikola Tesla ( 1856-1943 ) as a means of generating very high voltage as well as power transmission. Richard has a great two hour video tape of his work which he will send to you for the following: ten bucks, a blank good quality tape, and a postage paid mailer. It is well worth it! His "big" coil is about 4' tall and fires continuous bolts of lightning from nine to fifteen feet! This is a point-to-point measure too so add in about 30% for the twists of the arc! I used to be into them when I was a teenager and had always thought about getting back into it but the stuff he is working on has convinced me! I will be working with a couple friends ( sharing work 'n money ) and we are starting work on parts of it this thanksgiving holiday. It is interesting too because the "classical" design for a tesla coil is quite different from the actual best design. The classical design goes for long thin coils ( maybe 30" by 3" dia ) and just two or three turns of wire for the primary whereas the actual best design calls for much shorter / fatter coils and lots of primary turns ( 10 - 15 ) My friends and I have arrived on a basic design - 6" diameter and 30" long, fixed spark gap, 12kV neon sign transformer and homemade capacitor. Richard mentioned that he once built one just like this and he was able to get 5' bolts! Anyway, the posts are well worth saving, send away for the video tape too - it makes for fantastic viewing! b WOW!! *Nice* spark, Nick! Nick? NIKOLAI, WAKE UP!! ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1126 Date: 11-23-93 23:43 From: David Tiefenbrunn To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ On 11-19-93 Richard Quick wrote to David Tiefenbrunn… RQ> New lab so far is looking good. Expensive, contractor wants RQ> $32.50 per square foot. Have you "shopped" the local contractors much? I would thing you could get a pretty good deal with the terrible resession were in.:) In CT things are still slow, anyway. RQ> BTW I will trade tapes happily if anyone has goodies I would RQ>be interested in. Video tape is an excellent way to archive RQ>our little projects; I agree. I still sometimes forget to get the dang thing before "throwing the switch" though. RQ> not only are they useful as a personal reference, but they RQ> are amazingly effective teaching tools. Nothing explains RQ> something like a coil project as well as the designer/ RQ> operator pointing to, and talking about, the operational RQ> working equipment. Of course, most of my projects haven't been as striking as the 10KVA Tesla coil, but it is nice to have them on record. BTW, is that Tesla Coil Builders Association sticker on the big control panel for real? I never in 1K years would have thought there was such a thing. Dave ! Origin: =Abbey Road BBS= Higganum, Ct. (203)345-7635 (1:320/5967) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1143 Date: 11-24-93 01:29 From: George Powell To: Richard Quick Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ I bet tesla was a fun person to live by..made the locals life real interesting.. ;) ! Origin: Fruity Dog Support (1:2460/21) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1125 Date: 11-25-93 11:59 From: Richard Quick To: Dave Halliday Subj: 1,000,000KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> Once again - THANKS! No problem DH> Also, just had a bit of a "conceptual" breakthrough - was DH> trying to see why 1/4 wave was best and then saw that this DH> is 1/4 wave reflected over a ground plane… DH> Makes a lot of sense ( arcs too ) Yeah, It took me a few minutes of looking at sine, then a 1/4 wave antenna before I realized what was going on and was able to conceptualize in my mind. Only then did Tesla's repeated use of the terms "fundamental note" and "harmonic" make sense. The length of wire vibrates electrically and is more or less the perfect analogy of a musical string. When the length of wire is wound to form a coil, it is simply compressed into a smaller volume where it can be efficiently excited. Now you can force that length of wire to accept SOME energy at any frequency, but the wire has a natural "hot spot" of resonance, just like a musical string has it's natural note. A function of the coil, and it's natural resonance, is such that it offers low impedance at the base for currents that match it's natural resonate frequency. So if the coil has a natural resonance of say 250 kHz, and current at 250 kHz is fed into the base, the coil will take it up. Current will flow. Current of any other frequency sees a very high impedance. But at the top of the resonating coil you do not see current. The coil "converts" the base current into a voltage at the other end. Since this voltage rises as you go higher and higher up the coil, and reaches it's peak at the top; Tesla was able to determine the voltage at the top of the coil is the first 1/4 wave voltage peak of the RF current fed into the bottom. A good term to introduce here is VSWR, for Voltage Standing Wave Ratio. The coil at resonance establishes a standing wave of the resonate frequency. The bottom of the wave is a low potential, such as your RF ground. From this low potential base, the standing wave is established, and voltage increases as we move higher up to the top of the coil. In order to get a handle on the true resonate frequency of a coil I use a signal generator, o'scope, and a frequency counter. The signal generator produces about a 2 volt signal that can be varied in frequency. I place a 1K resistor between the signal generator output and the o'scope input. Now the o'scope measures voltage. The higher the wave on the scope, the higher the voltage present in the signal generator output. The output of the frequency generator is fed to the base wire of the coil, and the frequency of the output is varied while watching the o'scope. When the frequency of the signal generator matches that of the coil, the coil takes up the current. Because current flows into the base of the coil at resonance, there is a voltage drop in the signal generator output line. This voltage drop is measured by the o'scope (across the 1K resistor) and is know as a "grid dip". The wave on the scope drops to nearly a flat line. When I see a grid dip I know I have matched the signal generator output to the coils natural resonate frequency. By also running a frequency counter connected to the signal generator, I can tell precisely the frequency of the input current. So in this little example, with a coil resonating at 250 kHz; the coil is resonating at 250 kHz and accepts 250 kHz current at the base. The current flow is high, the base impedance is low. As you measure voltage up the coil, the voltage rises until you get to the top of the coil. At the top of the coil you find the maximum voltage peak. This is the first voltage peak of the RF current fed into the base, and represents the 1/4 wave point of the input frequency current. So you have a 250 kHz coil, with a 1/4 wave voltage output. 250 kHz input, 1/4 wave voltage output, helical resonator; or 250 kHz 1/4 wave Tesla coil. We know the coil does not require current fed to the base to become excited. Oscillating magnetic field flux at the resonate frequency will highly excite the coil. The coil also having the property of inductance. So the coil can become highly excited by placing it in close proximity to a high powered oscillator, which is the Tesla tank circuit. Excitation by field flux produces equal engery output from both ends of the coil. Current from the bottom, and voltage from the top. It becomes clear now why such heavy RF grounds are required for Tesla coil work, and why the RF ground must be isolated from all other equipment. DH> ::Status report:: DH> Got some PVC pipe - flimsy stuff but I will use wooden DH> braces to hold it circular while I wind it. Actually, will DH> probably cut out some plexi circles and glue them in… Plug the ends of the coil form with something to hold it round while it is wound. Once wound, the wire will stiffen the coil form and hold the shape. When you glue the endcaps on the form, it will be plenty sturdy. DH> Question - there are some very cheap cutting boards DH> available made out of a high-density polyethylene plastic - DH> was thinking of using them for the "breadboard" for the DH> transformer protection stuff as well as the base of the coil DH> - do you have any feedback on the Q of this material? Pretty good choice of material for for a filter board. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1244 Date: 11-26-93 01:00 From: Guy Daugherty To: George Powell Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ GP>I bet tesla was a fun person to live by..made the locals life GP>real interesting.. GP>;) You might say it brightened up their lives. Brought a little spark into them, so to speak. ! Origin: The Silhouetter bbs (209)472-0843 USR DS V32terbo (1:208/216) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1209 Date: 11-26-93 23:28 From: David Tiefenbrunn To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ On 11-23-93 Richard Quick wrote to David Tiefenbrunn… RQ> DT> *Quite* awesome… Previously the largest Tesla coil RQ> DT> I had seen was in a science museum in Boston, MA. RQ> DT> It's spark was maybe 1/2 of the >small< coil in your RQ> DT> video. I *used* to think it was a big one. RQ> RQ> Yup, we have one in our science muesum too. Small system RQ> putting out about 2' of spark. I decided I could do a little RQ> better if I put my mind to it. You shure did. :) RQ> DT> At what power level does it become dangerous to RQ> DT> draw spark with the pole? RQ> RQ> This is a very good question. Very good. I routinely pull RQ> spark off of my coils with a key, pipe, or other conductor. … RQ> Power arcs leaving the body and hitting the ground are very RQ> dangerious, especially for those who are more shock RQ> sensitive than myself. I do not experience "shocks" in these RQ> instances, but do feel the RF burns. I have also had a few RQ> F burns from change, keys, etc. on my person, as well as RQ> having lost all the magnetic strips on my bank and credit RQ> cards. My brother lost a nice digital watch once. RQ> RQ> But, if you know what you are doing, and the system is well RQ> set up in proper tune, it is OK to take up to 5 kVA output RQ> through a conductor to your person. But this is not R RQ> recommended for amateurs. Reminds me of one of my dad's T shirts: I am a professional. DON'T try this at home. You should get one :) It would seem that the important thing is to not allow a spark to jump directly to or from the body. The first coil I made (back in grade school days) only threw a spark about 1/2 inch long. But I could let it jump directly to a finger with no shock or burn. Not enough power to do damage. I do feel shocks (and burns), so I would hesitate before trying that with a large coil. RQ> DT> I'm going to show a few friends your tape. RQ> RQ> Please do. All I ask is that you do not make copies without RQ> my permission. O.K. ! Origin: =Abbey Road BBS= Higganum, Ct. (203)345-7635 (1:320/5967) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1150 Date: 11-27-93 00:52 From: Richard Quick To: David Tiefenbrunn Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DT> On 11-19-93 Richard Quick wrote to David Tiefenbrunn… RQ> New lab so far is looking good. Expensive, contractor wants RQ> $32.50 per square foot. DT> Have you "shopped" the local contractors much? DT> I would thing you could get a pretty good deal DT> with the terrible resession were in.:) In CT DT> things are still slow, anyway. Yeah, I'm going to go "shopping" as soon as I can get motivated to spend 100G. Right now I am catching my breath from the sticker shock. The building should go up fast, and I don't plan to start until spring or early summer. This will give me a chance to shop around. DT> BTW, is that Tesla Coil Builders Association sticker DT> on the big control panel for real? I never in 1K years DT> would have thought there was such a thing. Yup It's for real. Tesla Coil Builders Association Harry Goldman #3 Amy Lane Queensbury, NY 12804 … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1151 Date: 11-27-93 01:26 From: Richard Quick To: George Powell Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ GP> I bet Tesla was a fun person to live by..made the locals GP> life real interesting.. There are several good (and true) stories about the local disturbances Tesla created. One of the best concerns an electromechanical steam powered oscillator he constructed. Now the oscillator was built to provide a constant frequency field current for a RF alternator in his radio work. But he played around with the thing. In New York he had a lab in the loft of a building for awhile, I don't have the exact address, but I can easily reference it if required. The building had a heavy iron center post in the construction. The post came up through the center of the loft and supported the roof peak. The base of the post was sunk into bedrock, and carried a considerable portion of the building load. Tesla bolted the oscillator output shaft to the post and fired it up. As steam pressure in the boiler increased, so did the frequency of oscillation. He sat in a chair and observed the effects of the mechanical vibrations on objects at hand. Each object having a resonate frequency would begin to vibrate and move as the frequency of the oscillator matched it. After about 30-40 minutes Tesla began to notice the building itself begin to sway, and saw beams unseat. He went to shut down the machine. To his dismay he found that his jury rigged steam line was too hot to approach, and/or the valve was seized. He looked around the lab for a minute or two and finally attacked the problem with an axe, severing the steam line and blowing clouds of live steam into the building. As the steam cleared, he heard a knock at the door. Two of New York's finest stood in the doorway. Now Tesla was apparently no stranger to dealing with the authorities. He explained to the cops that they had arrived too late for the demonstration, and that an unfortunate problem prevented him from reproducing the test while they waited. He invited them back later in the day, and showed them out. It seems the police had received frantic calls from people in a radius of several blocks reporting an earthquake. Walls, sidewalks, and foundations cracked, windows shattered, street lamps tilted askew, and stuff was falling out of cabinets and shelves. The police realized that the station itself was only subjected to a slight tremor, but officers reporting to the scene of the calls found the intensity increased as the drew near Tesla's lab. It did not take them long to figure out where the commotion was comming from. As I mentioned, Tesla was no stranger in dealing with local authorities. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1266 Date: 11-30-93 12:15 From: Richard Quick To: David Tiefenbrunn Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DT> At what power level does it become dangerous to RQ> DT> draw spark with the pole? RQ> This is a very good question. Very good. I routinely pull RQ> spark off of my coils with a key, pipe, or other conductor. DT> … RQ> Power arcs leaving the body and hitting the ground are very RQ> dangerious, especially for those who are more shock RQ> sensitive than myself. I do not experience "shocks" in these RQ> instances, but do feel the RF burns. I have also had a few RQ> RF burns from change, keys, etc. on my person, as well as RQ> having lost all the magnetic strips on my bank and credit RQ> cards. My brother lost a nice digital watch once. RQ> But, if you know what you are doing, and the system is well RQ> set up in proper tune, it is OK to take up to 5 kVA output RQ> through a conductor to your person. But this is not RQ> recommended for amateurs. DT> Reminds me of one of my dad's T shirts: DT> I am a professional. DON'T try this at home. DT> You should get one :) DT> It would seem that the important thing is to not DT> allow a spark to jump directly to or from the body. Yes I would tend to agree with this, especially at higher powers. The charge density and amount of power alone can be dangerious, despite the output of the coil being clean RF. I don't know if the resolution on the tape is good enough to see but in the shot where I am pulling a few feet of spark off the coil with a copper pipe, there are some 6" - 8" sparks comming off my feet. Since I am standing on an insulated platform, and my shoes socks are sweaty, I only get a tingling sensation. Another thing to caution about is being in series with a power arc from the discharge terminal, even if the actual arc leaves a conductor such as a pipe or what not. Again the charge density is just too high on a big coil to make this safe. I have been placed in an uncomfortable position or two where this has happened, and the operator of the coil needs to have a cool head and be very familiar with the controls. I wish I had these incidents recorded on video tape. When doing the million volts through the body trick, or other HV RF experiments when in physical contact to the output, discharge must be radiated or arced through the air, not to ground. Power arcs to ground while in series with the circuit is "eye opening" to say the least, and can make your fillings really sing. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2224 Date: 12-01-93 00:01 From: Dave Lyle To: Richard Quick Subj: 1,000,000Kva Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>coil "converts" the base current into a voltage at the other RQ>end. Since this voltage rises as you go higher and higher up RQ>the coil, and reaches it's peak at the top; Tesla was able to RQ>determine the voltage at the top of the coil is the first 1/4 RQ>wave voltage peak of the RF current fed into the bottom. Richard, GREAT series of articles here. Just a quick question here. First, I understand what is happening as far as the 1/4 wave length is concerned. I relate this to transmission line theory, where the VSWR is approaching infinity. My question though, is..how does the coil excite at other odd multiples of 1/4 wave, i.e. 3/4, 5/4 wave? I suspect it would be more lossy, but what, if any, benefits might be derived by operating at the higher frequency? Dave ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1390 Date: 12-01-93 12:37 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> Status report: RQ> DH> Got the wire for the secondary as well as the basic RQ> DH> design. RQ>OK, I got some soft figures for you. Given the specs of the >planned coil you gave me here's what your looking at: RQ>Bare secondary frequency around ~260 kHz >Secondary top loaded with 18" diam, 4" cross section toriod >will resonate around ~180 kHz Great! I will be using a torrid so I will make it this size. RQ>These numbers are going to off a little, but I tuned a guys >coil once over the telephone when he was six states away. I >was throwing stuff off the top of my head. Stuff like that is so much fun when it happens <grin> I am called to do computer diagnoses over the phone a lot and it amazes people that I can just listen to them for a few minutes and then rattle off a list of keys to hit… RQ> DH> Also, found a *wonderful* three terminal plus ground RF > DH> filter for 240 volt @ 60 Hz rated at 60 amps! $20 - > DH> couldn't resist! RQ>I would have picked it up too. This is looking good, be sure >to run the filter backwards. If your using only one filter, >place it between in the supply line before the variac. Ground >the case to your 60 cycle neutral. Great! I didn't think about hooking it up "backwards" but that makes perfect sense! I will be just using that one filter so that is where it will be connected. RQ> DH> Still looking for a source of the form for the secondary > DH> the stuff I saw at a local Home Depot was poorly out of > DH> round… > DH> Maybe some plexiglass disks glued inside to maintain > DH> shape. RQ>I would avoid using baffels inside the coil form, they tend to >reduce the Q of the coil. Find a different supplier for some >rounder pipe before you go this route. That was my opinion too - it would give an electrical "bump" in the tube, not something to have in a tuned system. RQ> DH> Have a bunch of 3/8" refrigeration tubing that I can use > DH> for the primary - RQ>Just fine for this sized primary coil, make sure it is long >enough, though you can braze in a splice for added length. OK - I mentioned in another post that I just have about 30' of it. I'll measure what the primary will take and then get some more. Got an Oxy / Acetylene torch so brazing pieces together is not a problem. RQ> DH> Still need to get the step-up transformer - already have > DH> a 12kV 30mA neon but the "potential" transformers you RQ>If you use 12 kv neons you will need about 120 ma total to >drive this coil to good spark. That's four 12,30s. I will be checking with some neon sign places in the next day for a couple more transformers. There is one fairly close by me that does a lot of "art" signs and stuff. RQ> DH> Anyway - work progresses - I will be busy during this > DH> "holiday" season, also the people that were interested in > DH> working with me are still very very much interested - > DH> showed the primary person your video and their jaw > DH> dropped <grin> RQ>His was not the first, and won't be the last!!! You should >have seen the look on MY face while I was running it! I was >20' away and under cover and the sparks looked like they were >going to wipe my nose for me. I can well imagine! There is a local park that is situated on Lake Washington near where I live, I have been toying with the idea of firing the coil off there, maybe out on one of the boat docks. Drop a bunch of Aluminum flashing over into the water for the ground. Could be kind of fun! Anyway, I will talk with you later. Dave b Did you put the cat out? I didn't know it was burning. ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1398 Date: 12-02-93 08:04 From: Brian Carling To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH>My friends and I have arrived on a basic design - 6" diameter DH>and 30" long, fixed spark gap, 12kV neon sign transformer and DH>homemade capacitor. Richard mentioned that he once built one DH>just like this and he was able to get 5' bolts! DH>Anyway, the posts are well worth saving, send away for the DH>video tape too - it makes for fantastic viewing! What is his address? ANy chance I could get the design details on your smaller unit? ! Origin: _The_Attic_ [301-428-1970] 14.4K v.32b - (1:109/423) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1420 Date: 12-03-93 08:25 From: James Woodruff To: Dave Halliday Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ Quoting Dave Halliday to Richard Quick ⇐- DH> I can well imagine - I also did PA systems for bands for a while and DH> some of the perceptions about power and signal grounds were amazing. DH> Not so much for their blind ignorance and lack of common sense but for DH> the fact that some of them were still alive <grin> My church does not ground their amps. Is this to prevent ground loops, save the expense of an extra wire,or blind ignorance? This Is on their mobile equipment that they clip onto the service entry panel.They also hook their stage lights to the same ungrounded circuit. p r e t t y scary uh? Please reply,so I can help them out. THANX … A penny saved is ridiculous……. -!- GEcho/386 1.01+ ! Origin: Trinity ]I[ BBS -=[ Oklahoma City ]=- (405)691-2377 (1:147/2777) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1575 Date: 12-04-93 15:52 From: Dave Halliday To: Brian Carling Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ BC>DH>My friends and I have arrived on a basic design - 6" diameter >and 30" long, fixed spark gap, 12kV neon sign transformer and >homemade BC>DH>Anyway, the posts are well worth saving, send away for the video tape >DH>too - it makes for fantastic viewing! BC>What is his address? ANy chance I could get the design details on your >smaller unit? OK - here is his address excerpted from a message: >a two hour video tape in exchange for: One blank (high quality) >VHS tape, a postage pre-paid return mailer, $10.00 to pay for my >time and effort in seeing that you get a high quality, two hour, >recording of my work. Note this offer is not made on my behalf to >make any money, and I am not resposible for anybody's safety >should they decide to replicate any of the experiments I perform. >I will send a glossy print for $1.00 and a SASE. RQ>Richard T. Quick II, 10028 Manchester Rd., Suite 253, Glendale, >Missouri, 63122, USA You could scale down the design but I feel that the amount of time and money involved would be about the same regardless of what size coil you are building so why not go for a bigger one. The one I am building is 6" diameter, 30" tall and is powered by a bank of four neon sign transformers. Richard says that a coil like this will be capable of consistent five foot long arcs. Down the road, I would like to experiment with a "pocket" coil or a tabletop model but you do need a very very good ground regardless of the size so this isn't something that you could take somewhere and casually set it up and expect to get good results. Anyway, keep tuned to this conference and I will be letting people know how things are progressing! TTYL - Dave ë:-) b QMPro 1.51 b Never Wear Battery-Powered Clothing to a Formal Event. -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2318 Date: 12-06-93 11:17 From: Richard Quick To: Joseph Freivald Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JF> For those of us who are wanna bees, What's a tesla coil, and JF> why does it get at least 10 posts per day? A Tesla Coil is an air core, RF resonate, transformer. It is a very efficient source of very high voltage RF energy. If it weren't for the problem I am having with my ASCII character set I would give you a wiring diagram. Basically you take a high voltage pulse discharging capacitor and connect it to a large heavy coil. The cap is charged with a high voltage power supply (neon sign xfrmr, potential xfrmr, or power distribution xfrmr run backwards). The circuit consisting of the cap and coil is excited by discharging the cap through a spark gap. This way current of hundreds of amps at thousands of volts oscillate through the coil. Frequency of oscillation is dependant on the number of turns in the coil and the size of the cap. This is the basis of the Tesla Tank circuit. The secondary coil or "Tesla coil" is a hollow form with several hundred turns of wire. This coil has a natural RF resonate frequency based primarily on the length of wire used in the winding. The tank circuit frequency is made to match the secondary natural frequency by tuning, changing the number of turns in the heavy primary coil or changing the value of the pulse discharging capacitor. When the tank circuit frequency is matched to the secondary frequency, and the coils are placed in close proximity, energy is exchanged and transformed. RF voltages in the megavolts can be achieved with very high efficiency. The tank circuit literally converts line current into a series of rapid pulse dicharges with peak powers in the megawatt range. A simple coil setup is capable of producing more or less continous spark discharges several feet in length, or longer. I cannot say why there are so many posts on the subject, except that the topic is interesting and I have had more than a few requests for information on these systems. I have sent out a few video tapes with some of the work I have done, and it has greatly accelerated the interest. My video features a coil system I built operating with 10,000 watts input power, generating peak powers of 22 megawatts, with a discharge voltage of between 3-5 megavolts (or more). The system is able to produce arcs of synthetic lightning that strike out up to 15 feet. I hope this answers your question. If you need any additional information, or have other questions, please feel free to post on this topic. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2319 Date: 12-06-93 11:33 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>A tank circuit with a small capacitor, and a large primary >inductance, will reach down to the lower frequencies of >operation. A tank circuit of this design will use less power, >and therefore require a smaller step up xfrmr. The capacitor >will be smaller, which further reduces the cost of the >system. DH> Makes a lot of sense! Efficiency, efficiency… Put every watt into the discharge! RQ>So to give some advice to my friend Dave Halliday, who is >building a 6" secondary coil sometime in the near future, >plan on winding a primary coil from a conductor material that >I have listed above, and use a conductor length of around 75 >feet. Your primary should end up about as wide as, or wider, >than your secondary is tall. DH> Got it! I was thinking of using some 3/8ths refrigeration >tubing but since the surface area is important, I'll probably >get a reel of 3/4ths or 1/2" tubing ( gotta check on pricing >first ) With a 6" secondary coil that is 24" high, 3/8" soft copper water pipe is perfect. My big coil uses 1/2" pipe and only gets slightly warm on the first and second turns after a five minute full power run. Balance the diameter of the pipe to the length of the primary conductor. 50' conductor use 1/4" pipe, 75' conductor use 3/8" pipe, 100' conductor use 1/2" pipe. When is doubt use the next size up. DH> Trade some videos / photos once I get something to show. COOL! … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 4 Date: 06 Dec 93 12:45:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> There is a local park that is situated on Lake Washington DH> near where I live, I have been toying with the idea of DH> firing the coil off there, maybe out on one of the boat DH> docks. Drop a bunch of Aluminum flashing over into the water DH> for the ground. DH> Could be kind of fun! I have fired and grounded off of water grounds exactly as you are thinking. They work great! Good Luck! I hope to see a spark shot or two soon. Bring the camcorder, and a 35 mm, and a few friends. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2323 Date: 12-06-93 13:11 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ OK, People who are interested in the TESLA VIDEO have not, are not, and will not be dissapointed. I will send a full 2 hour SP recorded, one off master, VHS tape with sections showing my big coil literally burning up the back driveway and striking everything within 11 feet (arcs as big around as my leg on some strikes). You must send $10.00, a self addressed postage pre-paid return mailer, and a blank, high quality VHS tape. Richard T. Quick II 10028 Manchester Rd. Suite 253 Glendale, MO 63122 USA Tapes are sent out within 48 hours from receipt of your package, there is no monkey business. The video is instructive: it shows several coil systems in operation, details on the power control cabinet, wiring, tuning and firing as well as sections on spark gaps, RF filter chokes, etc. I also fire my "pole pig" utility power distribution transformer in a Jacob's Ladder at 8000 watts with 20,000 volts across the rails. This tape is my cutting edge 1/4 wave Tesla work, and involves lots of high voltage set ups and demonstrations. Due to the nature of the work covered on the video: I CANNOT BE RESPONSIBLE FOR THE SAFETY OF ANYONE ATTEMPTING TO REPRODUCE ANY OF THE SYSTEMS OR EXPERIMENTS FEATURED ON THE VIDEO!!!! I am more than happy to answer any questions or respond to comments in this area on anything covered on the video. I will also trade tapes even with people who are engaged in similar or other work of interest: Tesla coils or other high voltage equipment in action, rail guns, laser setups, taser guns, particle accelerators, capacitive discharge machines, etc. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2320 Date: 12-06-93 13:12 From: Richard Quick To: Dave Lyle Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DL> Richard, DL> GREAT series of articles here. Thanks! Another vote of confidence! DL> Just a quick question here. First, I understand what is DL> happening as far as the 1/4 wave length is concerned. I DL> relate this to transmission line theory, where the VSWR is DL> approaching infinity. You are correct in this relation. Transmission line theory does apply to Tesla secondaries. DL> My question though, is.. how does the coil excite at other DL> odd multiples of 1/4 wave, i.e. 3/4, 5/4 wave? I suspect it DL> would be more lossy., but what, if any, benefits might be DL> derived by operating at the higher frequency? Coils that are excited or driven to higher harmonics (over 1/4 wave) break down prior to the top turns. For instance a coil driven to 3/4 wave resonance would still break down at the 1/4 wave point of the winding. This problem is commonly seen on coils that are overdriven or overcoupled, and I cannot imagine any way to insulate against this breakdown. Higher harmonics CAN be reached by using two or more coils driven from the same tank circuit or by placing the primary in the center of a single coil. For instance a 1/2 wave system could be built using two coils, or driving one coil from the center producing two 1/4 wave peaks, one at either end. The trick to efficiency is to excite at a LOWER harmonic (below 1/4 wave), ie: 1/8th wave, 1/16 wave, or 1/32 wave. These lower harmonics are high in current, and lower in voltage. Loss is reduced because the lower voltage leaks less, and the energy of the wave is a product of both current and voltage. The 1/8th wave harmonic appears to be the most efficient. Now remember that we have not changed the frequency. The system frequency may remain the same, we are simply tapping the energy further back in the wave form. Tesla was able to force the secondary into these lower harmonics by the addition of the extra coil to the system, then reducing the number of turns in the secondary until it was 1/8th wave resonate. Current and voltage were then fed to the base of the extra coil resonator. The advantages of using the extra coil, and tapping the secondary energy at a lower harmonic are many: Coupling between primary and secondary may be tightend up considerably, driving more energy through the system; the 1/8th wave output of the secondary contains 70% of the wave energy as opposed to the 50% obtained in 1/4 wave output; there is much less voltage stress on the secondary which reduces the incident of breakdown and "splitting" (parasitic 1/4 wave peaks); current is removed from the secondary by transmission line to the extra coil, unloading the secondary for more input (allows higher break rates in the gap = greater throughput) and placing the main system VSWR in the uncoupled end resonator (extra coil); impedance, resistance, and distributed capacitance are also reduced with proper design and construction. This production of a lower harmonic from the secondary by adding the extra coil to the system is a true breakthrough in Tesla power processing. This is the three coil Tesla Magnifier as Tesla developed to industrial porportions in Colorado Springs, and may be scaled back for very efficient "basement" systems. I have seen Magnifiers producing 100"+ arcs at 4100 watts input power, and have myself hit 72" with inputs around 2500 watts. I see a real gain of 40% in spark length for input power with this system. Thank you for your input on transmission line theory and your question. I hope I have given a resonable and satisfactory response. If you have any other questions or coments I would be more than happy to reply to them. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2324 Date: 12-06-93 13:25 From: Richard Quick To: Brian Carling Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Brian Carling to Richard Quick ⇐- BC> Richard - what is your address please? BC> I'd like details on sending for your $10 video about Tesla BC> generators. Thanks - Brian C. You mispelled my name so this request did not come up in my personal mail scan. See my post of today to "ALL" for details of the Tesla Video. As I have said before, and several regulars in the conference will attest to, the video is first rate. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1471 Date: 12-06-93 13:26 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> Hi Richard - little note here - I don't know if you get a DH> British magazine called "Electronics World + Wireless World" DH> ( it used to be just Wireless World ) but the current issue DH> - November 1993 - arrived today and it is one to look at. RQ>Yes, since you offered, please copy the article and send it >to me. I would be in your debt. This looks like an >interesting system. DH> In the mail this afternoon! Thanks a lot. I just got back from a weekend in Chicago with my new girlfriend (NICE!) and look forward to seeing it! … 9 out of 10 men who try Camels prefer women _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1655 Date: 12-07-93 11:29 From: Dave Halliday To: Brian Carling Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ BC>DH>RQ> DH> Have a bunch of 3/8" refrigeration tubing that I >DH> > DH> can use for the primary - BC>DH>RQ>Just fine for this sized primary coil, make sure it is long >DH> >enough, though you can braze in a splice for added length. BC>DH>RQ>His was not the first, and won't be the last!!! You should have >DH> >seen the look on MY face while I was running it! I was 20' away >DH> >and under cover and the sparks looked like they were going to >DH> >wipe my nose for me. BC>I am a rank beginner, but have some good background education in >electronics/electricity… Can you help me get started? >I want to build a large Tesla coil. I'm also interested in Van de Graaf >generators etc. I don't want to build something puny! I like the idea >of building with refrigeration coil type copper tubing - that sounds >like serious high power. I've built my own linear amplifier before >(not a kit!!) I'm watching the posts from you and Richard with great >interest! Hi Brian - best thing to do would be to jump right in! I hadn't touched the stuff myself since high school but Richard's info is really clear and his video tape is well worth getting. The 6" dia / 30" long coil that my friends and I are building should be capable of a 5' arc so although this doesn't quite qualify as "large" it should be enough to make the neighbors *really* start to wonder about me ( not that they don't already ) There is a basic "learning curve" that needs to be accomplished and I think that it would be best to do this on a medium sized coil such as the one we are building - then progress to a monster <grin> Also, the really large coils need a really large source of high voltage to power them ( power company distribution transformer ) and they are very very loud - I think that Richard's 10" dia coil is about the upper limit to home built coils ( it throws 10 to 15 foot arcs ) I was also into Van de Graaf generators too in high school - used cake pans for the dome and was able to get 4" sparks on a dry day. Didn't have access to the tools to make a spun aluminum dome so the rolled edges of the pans were the upper limiting factor for voltage. Anyway, save all of the posts and send away for the video, get some thin-wall PVC tubing and a couple thousand feet of magnet wire, some neon-sign transformers, make one of the capacitors detailed in an earlier post and fire away! TTYL - Dave b QMPro 1.51 b "Bother", said Pooh, and deleted his message base… -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1654 Date: 12-07-93 11:36 From: Dave Halliday To: James Woodruff Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JW> DH> I can well imagine - I also did PA systems for bands for a >while and some of the perceptions about power and signal >grounds were amazing. JW> DH> Not so much for their blind ignorance and lack of common > DH> sense but for the fact that some of them were still alive <grin> JW> My church does not ground their amps. Is this to prevent ground > loops, save the expense of an extra wire,or blind ignorance? This > Is on their mobile equipment that they clip onto the service entry > panel.They also hook hook their stage lights to the same ungroun- ded > circuit. p r e t t y scary uh? Actually, if they are making a three wire connection directly to the service panel, they should be OK. You might want to get an outlet tester from your local radio shack or hardware store and verify a proper connection. These testers are three-prong plugs with three lights in them. The way the lights light up show how the socket is wired. If they are just using two wires to power a mobile electronic setup, they could be letting themselves in for quite a liability suit when a performer touches something in contact with the earth at the same time they are in contact with a metal part of the sound system. A band I used to do sound for had such a bad wiring setup that the guitar player could not get close to the microphone for fear of getting shocked. They took it with a grain of salt but we are dealing with a potentially lethal situation here. The first thing I did was to get their electrical system in order - no more shocks! It would be a very good idea to look into this - good luck! Dave b QMPro 1.51 b "Call waiting", great if you HAVE two friends… -!- WM v3.10/92-0434 ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 07 Dec 93 17:20:00 From: Richard Quick To: Dave Lyle Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ I thought I would take a minute and expand a little more on the subject of harmonics in Tesla systems. This should give you a better idea of how these harmonics can be used, and help me to better organize my thoughts on this very interesting subject. I talked yesterday about theory. Today I would like to discuss a little more practical application. Let me look at a system that I have actually built and fired. I have a normal Tesla secondary that resonates at about 200 kHz with a discharge ternminal. When this coil is placed in a primary and critically coupled, it will fire when the tank circuit is tuned to 200 kHz. No problems here, this is a normal 1/4 wave system. The tank circuit oscillates at 200 kHz, the secondary coil with discharger resonates at 200 kHz, and the output from the system is the 1/4 wave peak of a 200 kHz signal. Now we remove the secondary from the primary and replace the secondary with a coil that is 1/4 wave resonate at 400 kHz. Take a heavy wire or pipe from the top of the 400 kHz coil and make a connection to the bottom of the 200 kHz coil, now placed some distance away. Leave the tank circuit alone. When we fire the system, the secondary (or "driver" coil) is still excited by, and resonating at, 200 kHz. The frequency of the system has not changed. What has changed is the output of the driver coil: It is no longer a 1/4 wave peak at 200 kHz, nor is it a 1/4 wave peak at 400 kHz (the natural 1/4 wave resonate freq. of this coil) it is 1/8 wave CURRENT at 200 kHz which contains significant voltage. The frequency of the system has not changed, nor has the natural frequency of any coil in the system. What we have done is forced a shift in a 400 kHz 1/4 wave output coil to a lower harmonic. In this case the coil is quite able to resonate for 1/8th wave current output at 200 kHz. The natural frequency of the coil does not change, nor does the tuned fre- quency of the system change. The 200 kHz 1/4 wave coil at the end of the system recieves high current 1/8th wave signal at 200 kHz. Now we have set up a system that opens up many opportunities for specialization and improvement. First thing that will be noticed is that the transmission line is highly energized but runs at a fairly low voltage by Tesla standards. We have removed the high voltage 1/4 wave peak from the secondary in the system, and the 1/4 wave peak is now located on the discharge terminal of the end resonator (the 200 kHz 1/4 wave "extra" coil). Simply removing the 1/4 wave peak from the top of the secondary has really reduced the stress on the system and allows for substantial increases in throughput. One of the most important factors here is that the 1/4 wave resonator (the extra coil) is allowed unrestricted VSWR. In a normal 1/4 wave system, with the 1/4 wave peak located on top of the secondary, the VSWR in the 1/4 wave coil is restricted by the field flux interaction between the primary and secondary. This field flux damps some of the VSWR resonance. Now the resonator is able to "ring" freely, without magnetic interferance. The secondary in the system (driver coil) is still damped by field flux, but we are no longer looking to this coil to perform substantial VSWR voltage gains. What we want from this coil is heavy 1/8th wave current. We are more than happy to get a simple ratio of turns transformation from this coil, but as it turns out we do get a significant VSWR voltage rise even on a coil forced into 1/8th wave resonance. However since we want current and not high voltage, we can couple this coil much much tighter to the primary. Increases in coupling coefficients by a factor of four may not be out of line in primary/secondary drivers fired under oil. Even in air, coupling coefficients may be doubled or even tripled. We may also use much heavier wire for higher Qs. As coupling coefficients (magnetic interaction between coils) are increased, energy transfer is increased. All of the sudden you can squeeze in nearly twice as much power, without drawing a single additional watt. In a normal 1/4 wave system, increasing the coupling would force a destructive breakdown of the 1/4 wave secondary, as all energy must be processed by the single resonator. But, with an extra coil, and an 1/8th wave driver, stress in the system is greatly reduced. The driver hands off current to the extra coil as fast as energy is pumped in from the primary, there is no high voltage 1/4 wave "pressure point" on top of the driver coil to stress the windings, and the VSWR is divided between two coils, not burdened on a single secondary. Another gain is realized by the fact that the output of the 1/8 wave resonating driver contains 20% greater energies than a 1/4 wave output. Why? Well the total energy in a wave form at any given point is a product of current and voltage. The 1/4 wave output has voltage, but theoretically has 0 current, as it is a peak on the wave form. The 1/8 wave harmonic however has voltage and current both, and both are porportionally at their highest value. In other words the 1/8 wave point is the location of the greatest energy available anywhere on the wave form. Here you find the highest value of voltage * current. It works out to 70% of the wave energy as opposed to 50% available at the 1/4 wave peak. So lets look again at what we have gained. Greater coupling between the primary and secondary for more efficent throughput. Higher VSWR in the 1/4 wave resonator (extra coil) by removing this coil from the damping effects of the magnetic field flux. Higher energy transfer between the driver and extra coil by using 1/8th wave current in the transmission line. These gains are easily realized before specific modifications are made to the tank circuit and coils to take advantage of the setup. Improve- ments can include higher break rates for more frequent excit- ation; heavier wire, higher Q coils; higher input voltages; and balanced capacitor tank circuits. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1649 Date: 12-07-93 21:50 From: Terry Smith To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> the drugstore. The only thing required was 56 hours of time in RQ> arranging the plates according to Bill. But he did end up with RQ> .03 uf 15 kv pulse capacitor in a five gallon bucket. It was RQ> quite a performer on his coil at 3600 watts! RQ> The novice coiler should think about the capacitor requirements RQ> and experiment some before beginning large scale homemade caps. Why not use a G3 mica or, for more current, a vacuum cap? With the time value and instability of what you're describing, it sounds like a couple hundred $$$ for a readily available commercial cap would be a good comparative value. What is the design ESR goal? Terry -!- Maximus 2.01wb ! Origin: Methylene Chloride: Melts your CPU, & your hand! (1:141/1275) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1701 Date: 12-08-93 07:46 From: Brian Carling To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH>BC>DH>My friends and I have arrived on a basic design - 6" diameter DH> >DH>and 30" long, fixed spark gap, 12kV neon sign transformer and DH> >DH>homemade DH>RQ>Richard T. Quick II, 10028 Manchester Rd., Suite 253, Glendale, DH> >Missouri, 63122, USA thanks for the info. I am going to see what I can find at the local library also. DH>You could scale down the design but I feel that the amount of time and DH>money involved would be about the same regardless of what size coil you DH>are building so why not go for a bigger one. No, I want to build the BIG one! DH>The one I am building is 6" diameter, 30" tall and is powered by a bank DH>of four neon sign transformers. That doesn't sound too huge to construct… Do you connect the neon sign transformers in series or what? DH>Richard says that a coil like this will be capable of consistent five DH>foot long arcs. Cool! DH>Down the road, I would like to experiment with a "pocket" coil or a DH>tabletop model but you do need a very very good ground regardless of the DH>size so this isn't something that you could take somewhere and casually DH>set it up and expect to get good results. Why can't the one you describe be a "table-top" model? 6" around by 30" tall would fit on most tables! DH>Anyway, keep tuned to this conference and I will be letting people know DH>how things are progressing! I'll watch eagerly! DH>— WM v3.10/92-0434 DH> ! Origin: Advanced Software Concepts-WC3.90P-15.8,301-794-6496 (1:109/546) * SLMR 2.1a * Environmental activists: Green on the outside/RED inside! -!- Maximus/2 2.01wb ! Origin: _The_Attic_ [301-428-1970] 14.4K v.32b - (1:109/423) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2418 Date: 12-08-93 16:34 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Thank you Dave for sending the magazine with the article on the spark gap transmitters. It was interesting, but full of mis- crediting. The author chose in many instances to detail the worst systems of the era. Research, patents, articles, legal trials, and public demonstra- tions produced by Nikola Tesla show conclusively that he was much more advanced in wireless transmission, yet the article reads "Marconi this… Marconi that… Marconi's work showed…" The circuits, schematics, and techniques shown in the article are quite primitive when compared to the circuits Tesla was using two, even three, years earlier. Processing efficiencies of energy in the circuits detailed in the article could only be considered poor at best. Tesla shows circuits published in 1891 that produce continuous wave undamped oscillations. The circuits are efficient, powerful, and frequency stable (no damping, drifting, or beating). Tesla's spark gap transmitters of a few years later were ranged by the U.S. Navy at over 1500 miles with 2.5 kVA input. His maritime transmitter design was commercialized by Fritz Lowenstein (I believe), and was a full head and shoulders above the units designed by people like Thompson and Marconi. The photos of the damped wave trains were very interesting. The author mentioned that the photos were made with reproduction equipment that resembled units of the era as closely as posible. I just find it galling that he would go through such efforts in accuracy this area and would only mention Tesla's name once. It was also interesting to note that the large 300 kVa Marconi transmitter discussed in the article was retrofitted once, and decommissioned early because the output was so highly damped. Looking at the material I can only imagine the nightmare of maintaining a sharp tune in the system, and the related problems with frequency drift and efficiency. Many of these problems are related to the poor gap design and lack of primary inductance. The gaps would not quench well at these power levels, and the short primary conductor does not provide sharp tune, good coupling coefficients or energy transfers. Tesla's systems of this era were much much more advanced. It has been documented in the U.S. Supreme court that Marconi stole a number of patents from Tesla relating to Tesla's early wireless work. The two men were in contact for nearly a year prior to 1890, during which time Marconi had substantial access to Tesla's ideas. When Tesla realized the theft of his unper- fected systems was becomming prevalent, he came to despise Marconi and cut him off of any new information. Afterwards Marconi was stuck for a number of years in his efforts to develop a powerful working transmitter, at least until he was able to steal Tesla's published patents for the coupled secondary/ antenna. Tesla by this time had raced ahead by leaps and bounds to the prototype development of the Magnifing Transmitter in the mid 1890s, while Marconi was still using primitive gaps and poorly coupled, short primaries for years. Tesla's Magnifing Transmitter was remarkably frequency stable, narrow band, continuous wave, and extremely powerful and efficient. Yet he, and credit for his work, has all but been deleted from main stream history. I can go on and on. Tesla was using high frequency alternators running 20,000 hz or more for his power supplies (patented) in his transmitters of this era, yet the article details the use of 500 hz alternators by Marconi. The result: Marconi's damped wave transmitter ran maximum synchronous break rates around 1000 BPS, (breaks per second) while Tesla went asynchronous to 40,000 or even 50,000 BPS and was able to achieve nearly undamped CW output. Marconi's machines were plagued with a heavily damped signal, short range, reception problems, high input powers, and very poor efficiency. The article noted that later; others went to high speed asynchronous breaks, but they lacked the oscillator circuits Tesla was running, and the sophisticated 1/8th wave driver system (Magnifing Transmitter) to utilize these extremely high break rates. When others tried running asynchronous breaks with extremely high BPS on 1/4 wave drivers, the performance fell off to near zero, and they called Tesla a liar. Indeed, Tesla was so far ahead with the system that NOBODY EVEN UNDERSTOOD THE CIRCUITS HE WAS USING UNTIL THE MID 1980s!!!! That is over 90 years later, not a mistype. Credit given to his less creative competition, men like Edison and Marconi, is wrongful, and not based in historic fact. Both Edison and Marconi advocated systems that failed the test of time and practicality, to be replaced with systems invented by the master, Nickola Tesla. Tesla's most advanced systems went unutilized completely, unless they have been incorporated into classified SDI projects for particle beam devices. I have seen this over and over. In Chicago last weekend at the Museum of Science and Industry; Edison gets a full sectional display, complete with an orignal model DC generator. DC power generation and transmission on industrial scales is dead in all but highly specific applications. Yet Tesla, the inventor of the modern AC industrial power grid gets not a word. The only mention of Tesla's name I could find was on a single "classic" coil on loan from the University of Chicago. BTW, the section in the article on the Wien quench gap manu- factured and used in transmitters by Telefunken, exactly corresponds to my post of over a month ago in this conference. Tesla was paid royalty by Telefunken on every transmitter produced until the start of WWI. These transmitters were on board every German U-boat, and Tesla's system was used on large land based transmitters used by the German command. Tesla offered these patents to the U.S. military several times, but was turned down. Needing money he sold them to the highest bidder, and the Germans praised them highly. The U.S. Navy bought Tesla transmitters prior to WWI from an intermediary company run by Fritz Lowenstein. Herr Lowenstein was a highly praised assistant to Tesla in New York and Colorado Springs. The patents as I have said were owned by German nationals, but Mr. Lowenstein had the technical expertise to see that they were properly manufactured and tuned. Tesla, as I have mentioned before, was notorious for not detailing important "tricks of the trade" in his patent applications; especially after his experience with Marconi and others. Having worked closely with Tesla, Lowenstein sought commercial applications from systems he felt were sufficiently perfected, though Tesla saw the Magnifier as the system to bring to industrial power levels. I want to thank you for sending the article. I enjoyed readng it nearly as much as I enjoyed tearing it to pieces. If you run across similar material please post me. I have copied my archives from this thread, including much material you may have missed, onto the disk you sent me. I am also going to copy the article from the magizine you sent, and I will return both shortly. I have had a very busy week, what with a weekend to Chicago, and a new girlfriend, so I am running a little behind. I still have not unpacked my suitcase. You should get your material returned around the time you get this post or shortly after. Thank you again for thinking of me. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1692 Date: 12-09-93 08:42 From: Terry Smith To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> By reading the Colorado Springs Notes it is quite clear that RQ> Tesla struggled to get a good ground on site for his system and RQ> cited the local geology (sand & rock) as the source of his RQ> problem. He eventually had to run water 24 hours a day over his RQ> ground. RQ> He used a two ground system in his CS lab, and documents the RQ> resistance, and electrical distance between the two. The system RQ> ground was a 3' square copper plate dropped in the bottom of a RQ> 12' hole with a couple of wheelbarrows of coke dumped on top. RQ> The hole was backfilled and watered as I mentioned. You'll find that some broadcasters in areas with problem soil use multiple 30' long 'salt' paste filled chemical ground devices near a tower base. In Florida, where serious lightning strikes are a problem, I've heard reports of the sand being melted, forming an insulating layer over such devices. An AM antenna system may have 2 to 20 miles of #10 bare copper wire, plus a large quantity of 4" strap, and expanded mesh copper screens, for grounding. That's several hundred pounds of Cu for a small system, and several thousand for a large one, aver an area of acres. This is done even on a wet site. Terry -!- Maximus 2.01wb ! Origin: Methylene Chloride: Melts your CPU, & your hand! (1:141/1275) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1599 Date: 12-09-93 11:03 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ I have spent a few hours and archived all of the posts from this thread. I have had several people ask repeat questions, and others inform me that feed problems have caused them to miss some material. If you are interested in getting a complete and up to date archive of all of this material, please mail me a floppy and a SASE. I will be happy to send you my archives free of charge. Richard T. Quick II 10028 Manchester Rd. Suite 253 Glendale, MO 63122 USA … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1600 Date: 12-09-93 15:01 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Dave, I shot the magazine back to you in the mail today after I made copies. I returned the disk you sent with it. On the disk I copied my archives from this thread, and you will find a personal letter. I am sorry that the archives are a little disorganized, but the posts were saved from two machines, and so there is some duplication. Everything of importance from about 10/5/93 is on the disk, though it may be scattered among several files. Everything including your letter are in standard DOS text. Look forward to seeing some video/photos of your coiling work soon. BTW did you really decide to lengthen the 6" coil form from 24" to 30" in height? I would think this would require more than the 1500' of magnet wire you had earmarked for this project. I was just curious. Also, I am seeing posts that you have quoted from others, but I am not seeing the original posts here…. This looks to be a network problem, unless these people are posting to you locally…. I wonder what is going on. I sent you a post last week mentioning that I saw you had made a local logon here to the SLUG BBS, we narrowly missed a chat. How long have you been calling locally? If you get the chance since it appears you have a high speed modem you can grab the thread here if you have any network problems. This board has nearly all of my original posts in this conference still available. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2509 Date: 12-10-93 16:15 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Terry Smith to Richard Quick ⇐- RQ> the drugstore. The only thing required was 56 hours of time RQ> in arranging the plates according to Bill. But he did end up RQ> with .03 uf 15 kv pulse capacitor in a five gallon bucket. RQ> It was quite a performer on his coil at 3600 watts! RQ> The novice coiler should think about the capacitor RQ> requirements and experiment some before beginning large RQ> scale homemade caps. TS> Why not use a G3 mica or, for more current, a vacuum cap? Mica is not as good for homemade caps as poly, they are lossy, and they get hot. Poly has a lower RF dissapation factor, is cheaper, and easier to obtain. Commerical mica caps that are found surplus may be used, but they are not as high Q as poly. Not many amateurs are running the vacuum systems or have the equipment and design skills to produce homemade vacuum caps. I have priced commercial units surplus, and would not find much use for a vacuum cap unless it was perhaps employed as a tuning cap on a small magnifier. TS> With the time value and instability of what you're TS> describing, it sounds like a couple hundred $$$ for a TS> readily available commercial cap would be a good comparative TS> value. Not for a simple hobbiest. Most coilers are looking for cost effective and flexible designs. They would rather put in the time stacking or rolling to build a cap cheaply, than send a check to the cap company for a custom commercial unit. After you have a few coils under your belt, and you can design systems that you know are going to require such and such values, you then start to look to a commercial unit to reduce size, increase efficiency, and reduce costs. This is more often true than not in large systems that grow from the work done with homemade or salvaged caps. 60% of the capacitance in my lab is homemade. Now if I added the total value of this capacitance against the cost of a single commercial unit, a commercial unit would be more cost effective, and this does not even include the time invested. But my homemade caps consist of 14 individual units. The number of units gives me voltage and value flexibility not available in one or two commercial units. To reproduce my homemade array in 14 commercial units would not be cost effective. Since I started small, I went homemade. As my work grew, so did my homemade capacitors. I already had most of the materials, had aquired the design and construction skills, and could increase my power levels with a couple days work building a few more caps. When I decided to go to the pole pig, I shopped for commercial caps to drive the system. I knew exactly the voltage rating that would be required, and the value I was going to need. Not paper values mind you: I had set the system up with homemade caps and juggled the system around to find the tune spots I wanted to hit. The bill on my two .05 uf 45kvac pulse caps came to $600.00, and I had to wait nearly two months for deliverly once I knew exactly what I needed. The bottom line on homemade caps is that they are cheap, built out of readily available materials, and offer high Qs. The instabilities are 90% resultant of poor techniques in construction or operation, such as dirty plates and dielectrics, trapped air, improper break-in of a newly constructed unit, or running with the gaps set to wide. Every failure I have experienced resulted from one of the above. Since the unit was homemade, I was able to repair the cap and return it to service. Built with cleanliness and durability in mind, homemade caps will work quite hard for a long time. It has been nearly a year since I have had any problems with a homemade unit. The designs I have mentioned work, give great spark, and are not too expensive to make for the beginner. If you want to pay $$$ for commercial units to experiment with, please feel free, the commerical units are quite good. Down the road a bit I will post the addresses of a couple of commerical manufacturers I have dealt with. Both of these companies have a $150.00 minimum order with a 6-8 week delivery wait. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2628 Date: 12-10-93 23:51 From: Dave Lyle To: Richard Quick Subj: 10Kva Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> I have a normal Tesla secondary that resonates at about 200 RQ> kHz with a discharge ternminal. When this coil is placed in a RQ> primary and critically coupled, it will fire when the tank RQ> circuit is tuned to 200 kHz. No problems here, this is a RQ> normal 1/4 wave system. The tank circuit oscillates at 200 RQ> kHz, the secondary coil with discharger resonates at 200 kHz, RQ> and the output from the system is the 1/4 wave peak of a 200 RQ> kHz signal. RQ> Now we remove the secondary from the primary and replace the RQ> secondary with a coil that is 1/4 wave resonate at 400 kHz. Hi Richard, I was actually wondering what would be the effect of going the opposite way. What if you removed the _primary_ and replaced it with one that resonated at 600 Khz. Now the secondary would be resonate at 3/4 wave, and the voltage/current distribution would be: At the base…………………….Current peak, Voltage null At the 1/4 wave point (1/3 of the way up the coil)…..Voltage peak, Current null At the 1/2 wave point (2/3 of the way up the coil)…..Current peak, Voltage null At the 3/4 wave point (Top of coil)……………….Voltage peak, Current null I suppose you would have trouble preventing a breakdown at the 1/4 wave (1/3 of coil) point, but would there be any advantages to the higher frequency operation? Origin: The County Line BBS Node1 414-476-8468 (1:154/100) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 11 Dec 93 01:16:00 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ BTW, I have several commercial micas that I have experimented with. The discharge from a coil using commercial micas tends toward a spindly, violet discharge with very little current behind it. The run times with these micas is very short, and I have damaged a commercial mica cap from overheating with very short runs times at fairly low voltage. The problem with commercial micas is really a combination of high RF dissipation factors, and the inability of most commercial micas to effectively pulse discharge. The homemade polyethylene caps give much superior performance. They don't get hot. In fact I have never even gotten a homemade cap warm. The reason for this is that poly has a very low RF dissipation factor, and when mineral oil is used as a coolant/ corona supressant there is very low loss, very little dielectric heating, and what heat does form is sunk to the oil. The spark from a coil run with poly caps is blue-white, thick, and violent with a hefty current peak behind it. Nearly all of the modern commercial caps designed for RF pulse discharging are plastic film types covered in oil. The difference between the two capacitor types is vast. Plastic film caps are much better performers in the Tesla tank circuit. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2035 Date: 12-11-93 18:37 From: Brian Carling To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH>Anyway, save all of the posts and send away for the video, get some DH>thin-wall PVC tubing and a couple thousand feet of magnet wire, some DH>neon-sign transformers, make one of the capacitors detailed in an DH>earlier post and fire away! Yes, unfortunately I missed many of the earlier posts… what is the capacitor for? What is it like? * SLMR 2.1a * The "World Series" _ISN'T_ !! -!- Maximus/2 2.01wb ! Origin: _The_Attic_ [301-428-1970] 14.4K v.32b - (1:109/423) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2647 Date:12-12-93 12:12 From: Robert Taylor To: Richard Quick Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Wanted to drop you a line & see if you got my post about a month ago on the book that Barnes&Noble has out called *The Inventions, Research, and Writings of Nikola Tesla*. Got a new catalog from them the other day & saw that their price had gone down to about $10. Good book w/ alot of the heavier technical stuff (including original schematics). Definately worth a look. ! Origin: BLUFF CITY BBS (1:123/70) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1733 Date: 12-12-93 14:19 From: Richard Quick To: Brian Carling Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH>My friends and I have arrived on a basic design - 6" diameter DH>and 30" long, fixed spark gap, 12kV neon sign transformer. BC> thanks for the info. I am going to see what I can find at BC> the local library also. Don't believe everything you read there, that is if you find anything at all. Detailed instructions on even the "classical" design Tesla Coils are as scarce as hens teeth. DH>You could scale down the design but I feel that the amount of DH>time and money involved would be about the same regardless of DH>what size coil you are building so why not go for a bigger DH>one. BC> No, I want to build the BIG one! DH>The one I am building is 6" diameter, 30" tall and is powered DH>by a bank of four neon sign transformers. BC> That doesn't sound too huge to construct… This (as far as I am concerned) is still a small coil. But as I have said it is just about right for a beginner. BC> Do you connect the neon sign transformers in series or what? Neon sign transformers have center tap grounded secondaries inside the case. You cannot run the seconmdaries in series for this reason. The secondaries are run in parallel for increased current output, while the voltage always remains the same. For instance, four 12 kv, 30 ma neon sign xfrmrs are wired to give 12 kv, 120 ma output. The primaries may be run in parallel as well, depending on your line power supply and variac. If you are limited to 120 volts input then you must run the primaries in parallel for 120 volts. If you have access to 240 volts lines, then it is best to get a 240 volt variac, and pair up the neon signs xfrmrs by placing two primaries in series so that 120 volts appears across each primary winding. Power factor correction capacitors are especially important if you are running neons at 120 volts. The amp requirements of four xfrmrs run at 120 volts without power factor correction can stress a normal household circuit. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1734 Date: 12-12-93 14:45 From: Richard Quick To: Terry Smith Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ TS> You'll find that some broadcasters in areas with problem soil TS> use multiple 30' long 'salt' paste filled chemical ground TS> devices near a tower base. In Florida, where serious TS> lightning strikes are a problem, I've heard reports of the TS> sand being melted, forming an insulating layer over such TS> devices. TS> An AM antenna system may have 2 to 20 miles of #10 bare TS> copper wire, plus a large quantity of 4" strap, and expanded TS> mesh copper screens, for grounding. That's several hundred TS> pounds of Cu for a small system, and several thousnd for a TS> large one, aver an area of acres. This is done even on a wet TS> site. I would concur with the practice of using such heavy RF and lightning grounds. My experience with Tesla systems shows that there really is no such thing as a grounding system that is too large. That profession radio systems are using such heavy grounds does not surprise me. The system needs to have a solid zero voltage point capable of grounding heavy current in order to establish a a powerful signal, not to mention protection from lightning, and for safety of the HV outputs in the transmitter itself. Tesla was the first person to have applied ground to a tuned circuit. He was the first to realize the advantages of heavy grounding, and the construction of extensive grounding systems. What is really surprising is the number of people who do not, or refuse to, appreciate ground requirements for high powered Tesla and radio equipment. My large coil featured in the video has equal energy output from both ends of the coil. While the discharge terminal produces visible output in 1/4 wave spark with energies of many megawatts at more than a couple of megavolts; the base wire is literally flooded with current. I have measured RF currents of over 60 amps rms with a current transformer in the base wire of this particular system, and despite the wave theory of zero voltage at this point, there is considerable voltage. If there is ANY resistance to this RF current problems begin. The only way to remove this current and still maintain low potential in the ground is to use heavier and larger grounding systems. I have seen heavy coronas, arcing and sparking, intense RFI, and highly RF energized control circuits in Tesla systems using inadequate grounds and/or ground paths. This not only affects coil performance, efficiency, and throughput of the system, it is also unsafe and unneighborly. A grounding system as you described would be ideal for high energy Tesla work. -!- … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 14 Dec 93 12:19:00 From: Richard Quick To: Dave Lyle Subj: 10Kva Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Now we remove the secondary from the primary and replace the RQ>secondary with a coil that is 1/4 wave resonate at 400 kHz. DL> I was actually wondering what would be the effect of going DL> the opposite way. DL> What if you removed the _primary_ and replaced it with one DL> that resonated at 600 Khz. Now the secondary would be DL> resonate at 3/4 wave, and the voltage/current distribution DL> would be: > At the base…………………….Current peak, Voltage null > At the 1/4 wave point > (1/3 of the way up the coil)…..Voltage peak, Current null > At the 1/2 wave point > (2/3 of the way up the coil)…..Current peak, Voltage null > At the 3/4 wave point > (Top of coil)……………….Voltage peak, Current null DL> I suppose you would have trouble preventing a breakdown at DL> the 1/4 wave (1/3 of coil) point, Trouble would be a mild word for it. The 1/4 wave voltage peak appearing in the windings would destroy the coil in short order. RF voltages in these frequencies just don't understand what "insulation" is. I have not found any practical material or construction technique that would contain the voltage of a solid 1/4 wave voltage peak that appears in the coil windings. Plate glass, 1/4" thick polyethylene, etc. are invisible to this discharge, and the energy passes right through it virually unimpeded. Mineral oil is the best insulator for this particular energy, but there is insufficient space between turns on the coil for sufficient breakdown protection. Even if there was enough room between turns, then you have problems with the coil form breaking down. I have done experiments with coils in which the same basic end result was achieved by bottom feeding an extra coil with current that resulted in higher harmonic resonances of the extra coil (such as the 3/4 wave harmonic you charted above). When the coil was fired, sparks and corona came flying out of about a dozen turns in the coil. Those turns where spark and corona appeared corresponded to the 1/4 wave peak. But there was no way to contain it. The sparks broke down the windings, scored, then carbonized the coil form . The coil suffered irrepairable damage and had to be scrapped. Similar incidents with other systems where energy densities were high resulted with the spark from 1/4 wave peaks in the winding blowing holes through the coil form. Again the coil was a complete loss and had to be scrapped. In addition to the breakdown, the remaining turns further up the coil had no energy at all to speak of. Why? All the energy in the system was lost to spark and corona leakage at the 1/4 wave breakdown point, insufficient energy remained in the coil windings above the breakdown to do anything. DL> would there be any advantages to the higher frequency DL> operation? None that I can think of. This model represents a very high loss situation. 1/4 wave voltage peaks represent the final output point in a coil system. There is no way to process the energy in wire to any point above 1/4 wave in a single coil without tremendious losses. However when you go to two or more coils, where you are working with more than one output terminal, it is possible to achieve 3/4 wave signal processing. This requires a pair of 1/8 wave driver coils, two primaries run in series off the same tank ciruit, and two extra coils. Your outputs from the extra coils are still 1/4 wave with the peaks on the terminals, but taken as a whole the system does efficiently process a 3/4 wave signal. This system would be adding up lower harmonics (two 1/8th wave outputs, with two 1/4 wave outputs) to get to efficient 3/4 wave signal processing. This system would be unique in that it may not require a ground, as the two tuned sets of coils could "beat" off of each other; in other words the nul voltage current output from the base of one 1/8 wave driver coil could be fed into the base wire of the second driver. This system would require that the series run primaries, and the drivers and extra coils be wound in opposite directions to achieve phase differential. The base wire current output of one coil becomes added input to the base of another. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2 Date: 14 Dec 93 12:33:00 From: Richard Quick To: Robert Taylor Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Robert Taylor to Richard Quick ⇐- RT> Wanted to drop you a line & see if you got my post about a RT> month ago on the book that Barnes&Noble has out called *The RT> Inventions, Research, and Writings of Nikola Tesla*. Yes I did. I take it then you missed my reply. I own a copy, and a copy of nearly everything else worthy of note on the subject. I have posted a bibliography for source material on his more advanced work. The book you mention is drawn from his public lectures and other "public domain" material. Things really start getting good when you access sources of material he produced that were never intended to become public. This private material, when combined with his patents and patent applications, reveals much larger plans. Thank for checking up, and the book does make very interesting reading. It covers some of his early work in good detail. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1811 Date: 12-14-93 13:55 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> There is a local park that is situated on Lake Washington > DH> near where I live, I have been toying with the idea of > DH> firing the coil off there, maybe out on one of the boat > DH> docks. Drop a bunch of Aluminum flashing over into the water > DH> for the ground. RQ> DH> Could be kind of fun! RQ>I have fired and grounded off of water grounds exactly as you are >thinking. They work great! Great to hear! RQ>Good Luck! I hope to see a spark shot or two soon. Bring the >camcorder, and a 35 mm, and a few friends. I am going out of town for fifteen days over the holidays but I should have something in a month or so after that. Have a lot of the raw materials - stuff for the capacitor. Need to get the neon transformers and actually wind the coil and build the base to hold the primary. Things have been extremely busy at the store so I haven't had too much "spare time" but January has always been pretty slow. Anyway, I am now getting the feed directly from SLUG-BBS so there should be no missing messages. TTYL - Dave ë:-) -!- b QMPro 1.51 b The Disk Crash BBS - now with 360K Online ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1812 Date: 12-14-93 13:56 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> In the mail this afternoon! RQ>Thanks a lot. I just got back from a weekend in Chicago with my >new girlfriend (NICE!) and look forward to seeing it! Sounds good! Gotta get me one of those sometime… Maybe after the coil is built… <grin> -!- b QMPro 1.51 b Work: the worst thing you can do for your health. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1813 Date: 12-14-93 14:08 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Thank you Dave for sending the magazine with the article on the >spark gap transmitters. It was interesting, but full of mis- >crediting. The author chose in many instances to detail the worst >systems of the era. I thought you would get a kick out of it. I had intended you to keep the magazine - that was why there was just the return mailer for the disk. If you want, I can pop it in the mail again. Anyway - I figured you would have some fun with the article. I have not made any major study of Tesla's life but what I have seen ( Man out of Time by Cheny (sp?) plus a couple other articles ) makes me realize that he is very much an un-sung hero of electronics. RQ>The photos of the damped wave trains were very interesting. The >author mentioned that the photos were made with reproduction >equipment that resembled units of the era as closely as posible. >I just find it galling that he would go through such efforts in >accuracy this area and would only mention Tesla's name once. Yeah - it is like he is just copying the "party line" of the people who claimed to "develop" the equipment without doing any research on his part… >The gaps would not quench well at these power levels, and the >short primary conductor does not provide sharp tune, good >coupling coefficients or energy transfers. Tesla's systems of >this era were much much more advanced. The three turn primary also caught my eye. Plus the capacitance was probably huge and lossy - oil filled wooden boxes… RQ>BTW, the section in the article on the Wien quench gap manu- >factured and used in transmitters by Telefunken, exactly >corresponds to my post of over a month ago in this conference. >Tesla was paid royalty by Telefunken on every transmitter >produced until the start of WWI. These transmitters were on board >every German U-boat, and Tesla's system was used on large land >based transmitters used by the German command. Tesla offered >these patents to the U.S. military several times, but was turned Now *that* is interesting! Anyway, on to the next message - TTYL - Dave -!- b QMPro 1.51 b New Resturant on the Moon. Good food but no atmosphere… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1814 Date: 12-14-93 14:10 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>I have copied my archives from this thread, including much >material you may have missed, onto the disk you sent me. I am >also going to copy the article from the magizine you sent, and I >will return both shortly. I have had a very busy week, what with >a weekend to Chicago, and a new girlfriend, so I am running a >little behind. I still have not unpacked my suitcase. Great! I got the disk - Thanks! I also went and got the entire thread from SLUG-BBS so I will have everything in continuous order. TTYL - Dave ë:-) -!- b QMPro 1.51 b Live long and phosphor… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2666 Date: 12-14-93 14:23 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Look forward to seeing some video/photos of your coiling work >soon. BTW did you really decide to lengthen the 6" coil form >from 24" to 30" in height? I would think this would require >more than the 1500' of magnet wire you had earmarked for this >project. I was thinking of 30" all along. That stays within the 1:5 aspect ratio limit. The thickness of the wire that I got will allow for 940 or so turns in 30" of length which works out right at 1500' feet of wire. RQ>Also, I am seeing posts that you have quoted from others, but >I am not seeing the original posts here…. RQ>This looks to be a network problem, unless these people are >posting to you locally…. I wonder what is going on. I had been using another BBS for the FIDO messages and they were having some problems with missing messages. I will be using SLUG-BBS from now on until I get my Planet Connect dish up and running. It is sitting in the store right now but I need to get on the roof and cut a hole through the ceiling for the feed- through and of course ( being Seattle ) it is raining pretty much continuously… Maybe August if I am lucky <grin> Anyway, when the dish gets set up, I will start my own FIDO feed to my BBS. RQ>I sent you a post last week mentioning that I saw you had made >a local logon here to the SLUG BBS, we narrowly missed a chat. >How long have you been calling locally? If you get the chance >since it appears you have a high speed modem you can grab the >thread here if you have any network problems. This board has >nearly all of my original posts in this conference still >available. I already grabbed them - I had called a few times from home but the modem I am using there is an older one and it sometimes hangs. I will be calling from the store now. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2667 Date: 12-14-93 14:30 From: Dave Halliday To: Brian Carling Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ BC>thanks for the info. I am going to see what I can find at the >local library also. Although I have not really researched Tesla's life all that much, from what I gather, he kept critical stuff from his patent applications because he had been screwed by Marconi and others. You need to read between the lines. DH> You could scale down the design but I feel that the amount of DH> time and money involved would be about the same regardless of DH> what size coil you are building so why not go for a bigger DH> one. BC> No, I want to build the BIG one! How big? DH> The one I am building is 6" diameter, 30" tall and is powered DH> by a bank of four neon sign transformers. BC> That doesn't sound too huge to construct… It struck me as a nice size - large enough to produce nice 5' arcs but small enough as not to overwhelm my workshop or my budget. BC> Do you connect the neon sign transformers in series or what? A combination - the transformers are 12kV at 30mA so I will get 24kV at 60mA by using four of them. DH> Down the road, I would like to experiment with a "pocket" DH> coil or a tabletop model but you do need a very very good DH> ground regardless of the size so this isn't something that DH> you could take somewhere and casually set it up and expect to DH> get good results. BC> Why can't the one you describe be a "table-top" model? > 6" around by 30" tall would fit on most tables! Yeah but I was thinking about one that was maybe 3" dia and 12" tall. That would be impressive if it threw out foot-long arcs and from what all of the other designs of this type do, the arcs are several times longer than the length of the primary. Imagine something sitting on the table, a foot tall and two feet or so in diameter ( the flat primary coil ) throwing off two foot long arcs! DH> Anyway, keep tuned to this conference and I will be letting DH> people know how things are progressing! BC> I'll watch eagerly! Hey - start planing something! Get some neon transformers, some stuff to make the capacitors and a bunch of magnet wire and start building! ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1900 Date: 12-15-93 00:13 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>You should also make sure to run any HV power supply off a >variable autotransformer (variac). This way output voltage to >the experiment may be controlled smoothly. DH> I already have a nice 5-amp which I am sure could take DH> momentary overloads. I'm afraid this won't serve except for the smallest test coil. »Sniff, Sniff, is that smoke I smell????« »Sniff« DH> There was a beautiful dual 240 volt Variac at Boeing DH> Surplus but it was part of larger DC power supply and they DH> wanted $700 for the whole thing. It was a good 15" in DH> diameter! Didn't catch the current rating - too dark to see DH> inside the case. Most likely you were looking at a 29 amp+ rated Powerstat, these are just the ticket. DH> I am seriously thinking of going back there and offering DH> them $100 cash just for the Variac and seeing if they will DH> take it… Like I said, these are just the ticket. Powerstats made by Superior Electric are top of the line and are the most common industrial units I have seen. Glom on this puppy if you can, and if you can't, keep looking for another one. Powerstats are gangable, and they are common surplus. If you get one, odds are down the line you will come across another that will match the first and you can bolt the housings together and parallel wire them for pole pig operation. A nice variac or two are about the only thing that you must plunk down $$$ for if you are serious about coiling. I paid $150.00 each for mine, and never looked back. If I see another you can be sure I will plunk $150-$200 again without batting an eye. The price for new Powerstats would curl your hair and loosen teeth. Now do you want to be sick? I was out in Richmond Virgina last summer visiting some coiling friends. They have a scrap yard there that would… well I can't use that language here. Anyway, Alex drives out in his van and picks up this cabinet loaded with meters, a plastic potted 5 kVA HV xfrmr, and a ganged array of six 45 amp Powerstats in NEW condition, complete with remote drive (geared, motor driven common shaft with remote unit)… Price… $45.00 for the whole load, and the springs on his van were sagging badly. They guys out there said that the yard takes them, uses a cutter to cut the copper off of them, cut the toroid cores up, and scrap them valued around $5.00 each. I priced his array new at over $4500.00 DH> Also, I just sent the application off to Harry Goldman for DH> the TCBA membership. Welcome aboard! If you told him I sent you then I get a free issue of the NEWS at no cost to either of us!!! Thanks! -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1901 Date: 12-15-93 01:33 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Thank you Dave for sending the magazine with the article on >the spark gap transmitters. I copied everything that I wanted. DH> Sometime in the next month or so, I will have to go through DH> and copy some other issues. They do an occasional DH> "History of Electronics" article. Fun stuff! I would be interested in seeing more stuff like this if it catches your eye. Referring to Tesla: RQ>He was THE electrical genius of his time. DH> I also think C. P. Steinmetz was an interesting character DH> but Tesla was way ahead of everyone. Steinmetz was by no means a slacker. He gave us a lot in his area of expertise. But when it came to bulk technique, research, and knowledge; Tesla was a head and shoulders above the crowd. (literally and figuratively) Tesla's genius spanned an important era in mankinds history. His foresight ranks with Da Vinci, and his technical abilities were second to none. He intellect was broad, where others were very narrow and focused. Tesla was a mechanical engineer, an electrical engineer, a radio engineer, and a visionary. I have seen credits that he was a graduate of the Univeristy of Prague, but research done there by others show that he was never even enrolled, though it is possible he audited classes. Indeed he did not have access to funds to pay for a higher education. Yet he handed (hand drawn) plans for the first AC induction motor to a shop foreman for construction. The motor worked perfectly without modification or adjustments, and the exact same design is still used today. Without missing a step he went on to design three, then four, then six phase motors. Along the way he designed the power grid to supply them. He did this not once in one area, but hundreds and hundreds of times in numerous areas during his working career. Steam powered electro-mechanical oscillators, high frequency alternators, bladeless turbines and pumps, viscosity speedometers, electrical oscillators, X-Ray machines, CW transmitters, wave guides, the list goes on, and on, and on. The work that he documented, patented, and/or published covers but a small but significant fraction of the discoveries and research he did. Most times he was moving so fast that he did not have time to write things down. A good example is the Colorado Springs work. He did incredible things with the large coils that are only appreciated today, long past the time his name has been dropped from the mainstream history books. In an interview after his return to New York (from Colorado Springs) Tesla made the headlines by stating he had detected wireless transmission from Mars. He stated he tuned the machine to the detected frequencies and made a reply. At the time he was of course thought to be wacko (as Guy Daugherty would put it). Marconi had not yet managed to send a reliable signal. Tesla had already set his large coils up, and experimeted with them connected to a relay type tone receiever (no superhets yets). His tuning and amplification circuits (unpublished designs) were so sensitive that in an era of "stone knives and bear skins" (remember the automobile was nearing invention in a few years) he was able to listen to pulsars through a telephone handset. Thus, using his coil setup exactly as pictured in the famous photos, he changed a few connections, and had successfully built and operated the first radio telescope. I will forgive him that his overactive imagination led him to believe he was recieving signals from mars, especially since the nearest pulsar is many light years further away, the signal is exceedingly weak, and radio had not been invented yet (by Marconi). The same coils operated X-Ray tubes of his design that took X-Ray photos at 100 feet. They also were able to cavity resonate the earth at frequencies under 30 kHz. In addition (using the same coils) he was the first (and last until 1988) to produce synthetic ball lightning. I could go on. The bottom line is the other famous names of the era were good, but they were narrow and clumsy compared to the light that Tesla threw. Someone mentioned a book from Barnes and Nobel: The Inventions Writings, and Research of Nickola Tesla. In the lectures published in the book, Tesla demonstrates a single terminal bulb with a brush discharge (1891). The book shows photos of this and several similar bulbs. Tesla clearly states that he sees a potential for this effect as an amplifier and detector. The "brush discharge" in this demonstration is a directed electron beam from the center terminal of the bulb to the glass. What he is demonstrating is the principal behind the electron microscope. Yet at the same time (within months) he patents a number of tuned circuits that still form the basis of radio today. It was a question of time, money, and resources. Electron microscopes or radio? Tesla must have figured radio was a priority (he patented), and threw hints out to the crowded lecture hall about electron microscopes (public domain) where they were not understood or followed up on. -!- … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2714 Date: 12-15-93 11:04 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Good Luck! I hope to see a spark shot or two soon. Bring the >camcorder, and a 35 mm, and a few friends. DH> I am going out of town for fifteen days over the holidays DH> but I should have something in a month or so after that. DH> Have a lot of the raw materials - stuff for the capacitor. DH> Need to get the neon transformers and actually wind the coil DH> and build the base to hold the primary. Things have been DH> extremely busy at the store so I haven't had too much DH> "spare time" but January has always been pretty slow. Great, then at least you are are in the planning stage and are organizing yourself for the various constructions. DH> Anyway, I am now getting the feed directly from SLUG-BBS so DH> there should be no missing messages. And no delay!!! … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2715 Date: 12-15-93 12:11 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Dave Halliday to Richard Quick ⇐- RQ>Thank you Dave for sending the magazine with the article on >the spark gap transmitters. It was interesting, but full of >miscrediting. The author chose in many instances to detail >the worst systems of the era. DH> I thought you would get a kick out of it. I had intended DH> you to keep the magazine - that was why there was just the DH> return mailer for the disk. If you want, I can pop it in DH> the mail again. No need. I copied everything that I wanted. DH> Anyway - I figured you would have some fun with the article. DH> I have not made any major study of Tesla's life but what I DH> have seen ( Man out of Time by Cheny (sp?) plus a couple DH> other articles ) makes me realize that he is very much an DH> un-sung hero of electronics. He was THE electrical genius of his time. >I just find it galling that he would go through such efforts in >accuracy this area and would only mention Tesla's name once. DH> Yeah - it is like he is just copying the "party line" of the DH> people who claimed to "develop" the equipment without doing DH> any research on his part… Exactly. Tesla developed and experimented with every type system mentioned in the article before the people credited for these systems. >The gaps would not quench well at these power levels, and the >short primary conductor does not provide sharp tune, good >coupling coefficients or energy transfers. Tesla's systems of >this era were much much more advanced. DH> The three turn primary also caught my eye. Plus the DH> capacitance was probably huge and lossy - oil filled wooden DH> boxes… Yeah, the signal generated by this system would have been highly eratic. The pulses would have been very intense due to the capacitor size, but the output had to be a far cry from being a "smooth" powerful signal. Tesla on the other hand was using a tiny capacitance in a "balanced" tank circuit with very close coupling, and extremely fast quenching, ultra high speed gaps. He processed only 250 kVA (50 kVA less input power than the large Marconi xmittr) in Colorado Springs, but his output was CW, frequency stable, beat free, RF signal. His power processing efficiency was over 70% from the supply line to the antenna mast. His antenna current was a modest 1100 rms amps, with a peak power in excess of 10 gigawatts. Not bad for a guy in 1900 with a shoestring budget and salt water/glass caps. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2716 Date: 12-15-93 13:28 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Dave Halliday to Brian Carling ⇐- BC>Do you connect the neon sign transformers in series or what? DH> A combination - the transformers are 12kV at 30mA so I will DH> get 24kV at 60mA by using four of them. Nope, won't work. Each secondary coil in the neon xfrmr is grounded to the core. This setup will not allow the secondaries to be placed in series. Other type xfrmrs may be placed in series, such as plate, potential, and pig xfrmrs, but not neons. The secondaries may be placed in parallel for higher currents, but you are voltage limited. This is OK really because you will have trouble making or finding caps that will hold up to 24 kvac pulse. The primaries on neons are not grounded. The primaries may be run in parallel, so you may gang up as many as you want at 120 volts as long as your circuit will stand up to the load (which may be surprisingly high if you don't use pfc capacitance). However for anything larger than 1.5 kVA you will most likely be looking hard at 240 volt operation to reduce the current load. In this case you may take two neons of the same rating, place the primaries in series, and throw 240 across the two units. The secondaries are all parallel wired to the high voltage buss, regardless of the arrangement of the primaries. This way really large power supplies may be built up slowly, by simply adding pairs of neons to the bank. I have run up to 12 neons (6 pairs wired for 240 volt operation) for power supplies in excess of 4 kVA for medium sized coil systems. Phasing is important in running banks of neons. Not all neons are wired in the same direction. If the primary or secondary coils are reverse wired on some units, they will cancel out other units. A little time may be required to make sure that all of the neons are wired in phase. Nothing special is required to do this, just identify the out of phase unit, and reverse the line power connections, or reverse the secondary connection to the HV buss. You should also make sure to run any HV power supply off a variable autotransformer (variac). This way output voltage to the experiment may be controlled smoothly. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1867 Date: 12-15-93 14:38 From: Richard Quick To: Scott Hoffman Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ SEZ Scott Hoffman to All ⇐- SH> Anybody know where i can get really, really, really, really, SH> really, really, BIG, BIG, Capacitors, that can handle SH> massive currents, and voltages. I need them for my laser SH> project. The caps I had have blown and I learned that the SH> manufacturer is out of business. I'm not talking Radio Shack SH> special order caps. either. The ones I have are the size of SH> car batteries. I wont bother giving the specs. ( I know some SH> of you geniuses can't do anything without specs. and SH> schematics, but I no longer have the documentation.) The SH> "really BIG" x 6 comment should give you an indication of SH> what i'm talking about. Uh…Some of you might ask what i SH> need a power supply this big for, for an ordinary laser. SH> well….it's no helium-neon. It's a 8 foot nitrogen laser. SH> And requires a pulse of current of massive proportions to SH> excite the atoms. Hope someone can help!!! This is the thread you need to be addressing if you are into high energy devices. You missed a number of very good posts here in regarding these giant type HV pulse discharging capacitors. Please be specific, I can supply any information you need on this subject as I have a lot of experience designing, constructing, and buying caps of this type. If your BBS carries any archives you should download about the last months worth of posts in this conference and scan this thread for an idea of what I am talking about. Post the value you need, and the voltage requirements. I work with Tesla Tank circuits that generally require at least 10 KVAC pulse discharging caps. In a DC application you can push a homemade cap of this type to 30-35 KVDC without a problem. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1869 Date: 12-15-93 17:15 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> RQ>Good Luck! I hope to see a spark shot or two soon. Bring the > >camcorder, and a 35 mm, and a few friends. RQ> DH> I am going out of town for fifteen days over the holidays > DH> but I should have something in a month or so after that. > DH> Have a lot of the raw materials - stuff for the capacitor. RQ>Great, then at least you are are in the planning stage and are >organizing yourself for the various constructions. Yeah - I have a really good idea as to what goes into the construction so any time I see something that would be useful, I stockpile it. I plan to continue building after this first one. My friend who is working with me is curious about building a small one. We were talking about something a foot tall, 3" diameter. Judging from the other coils, it might be good for two foot arcs. RQ> DH> Anyway, I am now getting the feed directly from SLUG-BBS so > DH> there should be no missing messages. RQ>And no delay!!! Yeah - the other BBS was really lax about mail runs. I went and got all of the FIDO - Electronics messages and have been going through and making a text file of the dialogue. TTYL - Dave ë:-) -!- b QMPro 1.51 b 15 of every stamp is for storage… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1871 Date: 12-15-93 17:28 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> BC>Do you connect the neon sign transformers in series or what? RQ> DH> A combination - the transformers are 12kV at 30mA so I will > DH> get 24kV at 60mA by using four of them. RQ>Nope, won't work. Each secondary coil in the neon xfrmr is >grounded to the core. This setup will not allow the secondaries >to be placed in series. Other type xfrmrs may be placed in >series, such as plate, potential, and pig xfrmrs, but not neons. Whoops… Shows what I know <grin> I thought the multiple transformers were for both current and voltage increase. RQ>The secondaries may be placed in parallel for higher currents, >but you are voltage limited. This is OK really because you will >have trouble making or finding caps that will hold up to 24 >kvac pulse. Makes sense! RQ>However for anything larger than 1.5 kVA you will most likely be >looking hard at 240 volt operation to reduce the current load. In >this case you may take two neons of the same rating, place the >primaries in series, and throw 240 across the two units. The >secondaries are all parallel wired to the high voltage buss, >regardless of the arrangement of the primaries. This way really >large power supplies may be built up slowly, by simply adding >pairs of neons to the bank. I have run up to 12 neons (6 pairs >wired for 240 volt operation) for power supplies in excess of >4 kVA for medium sized coil systems. OK - I see where I got off the track - you were referring to pairs of transformers, I thought they were running in a series-secondary mode… RQ>You should also make sure to run any HV power supply off a >variable autotransformer (variac). This way output voltage to the >experiment may be controlled smoothly. I already have a nice 5-amp which I am sure could take momentary overloads. There was a beautiful dual 240 volt Variac at Boeing Surplus but it was part of larger DC power supply and they wanted $700 for the whole thing. It was a good 15" in diameter! Didn't catch the current rating - too dark to see inside the case. I am seriously thinking of going back there and offering them $100 cash just for the Variac and seeing if they will take it… Also, I just sent the application off to Harry Goldman for the TCBA membership. TTYL - Dave ë:-) -!- b QMPro 1.51 b In New Guinea: cargo cults. In the U.S.: vaporware. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1870 Date: 12-15-93 17:29 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> RQ>Thank you Dave for sending the magazine with the article on > >the spark gap transmitters. It was interesting, but full of RQ> DH> I thought you would get a kick out of it. I had intended > DH> you to keep the magazine - that was why there was just the RQ>No need. I copied everything that I wanted. OK - I'll keep it here then. Sometime in the next month or so, I will have to go through and copy some other issues. They do an occasional "History of Electronics" article. Fun stuff! > DH> I have not made any major study of Tesla's life but what I > DH> have seen ( Man out of Time by Cheny (sp?) plus a couple > DH> other articles ) makes me realize that he is very much an > DH> un-sung hero of electronics. RQ>He was THE electrical genius of his time. I also think C. P. Steinmetz was an interesting character but Tesla was way ahead of everyone. Anyway, TTYL - Dave -!- b QMPro 1.51 b I need a cordless extension cord, please ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2797 Date: 12-16-93 09:05 From: Tom Moeller To: Scott Hoffman Subj: Re: Big Caps. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ SH> Anybody know where i can get really, really, really, SH> really, really, really, BIG, BIG, Capacitors, that can SH> handle massive currents, and voltages. I need them for my SH> laser project. The caps. I had have blown and i learned SH> that the manufacturer is out of business. GE Capacitors in Fort Edward, NY makes some "large" capacitors… will 1.1uF at 62.5kV do? Their 30F1400 series goes from 5kV to 62.5kV, in sizes from 8x4x5.5 inches up to 13.5x6x16.5 inches. The information book I have here doesn't list any specs (oops! Sorry!) for the Effective Series Resistance (ESR) so you might check with their applications department before sending them your VISA number. SH> The ones I have are the size of car batteries. I wont SH> bother giving the specs. ( I know some of you geniuses can't SH> do anything without specs. and schematics, but I no longer SH> have the documentation.) Oh, sorry, you're right. I guess all the "geniuses" here shouldn't answer your plea for help. |-} SH> Some of you might ask what SH> i need a power supply this big for, for an ordinary laser. SH> well….it's no helium-neon. It's a 8 foot nitrogen laser. SH> And requires a pulse of current of massive proportions to SH> excite the atoms. I know an engineer (oops, another genius!) who worked on a laser drilling system - high accuracy pinholes thru titanium. He says his capacitor bank was made out of similar sized capacitors, with inductors in series along the way. By changing the connections and ratios of capacitance and inductance, they could change the pulse duration of the laser blast. Theirs was a flash-excited CO2 laser, though, instead of nitrogen. - Tom -!- EZPoint V2.1 ! Origin: Encore Electronics (1:267/14.42) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1903 Date: 12-16-93 10:55 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>RQ>You should also make sure to run any HV power supply off a > >variable autotransformer (variac). This way output voltage to > >the experiment may be controlled smoothly. RQ> DH> I already have a nice 5-amp which I am sure could take > DH> momentary overloads. RQ>I'm afraid this won't serve except for the smallest test coil. »>Sniff, Sniff, is that smoke I smell????« »Sniff« Drat… I'll just keep it on my service bench then… RQ> DH> There was a beautiful dual 240 volt Variac at Boeing RQ>Most likely you were looking at a 29 amp+ rated Powerstat, these >are just the ticket. RQ>Like I said, these are just the ticket. Powerstats made by >Superior Electric are top of the line and are the most common >industrial units I have seen. Glom on this puppy if you can, and >if you can't, keep looking for another one. Powerstats are >gangable, and they are common surplus. If you get one, odds are This one was a dual unit. I will try an offer - see what they say. The unit has been there for a few months so they might be tempted. The console that the Variac is mounted in is similar to your power control console - about 5 feet tall, the top third is sloped. I might just offer them $100 cash for that part of it. The DC supply that it connects to is in a 55 gallon drum. RQ>A nice variac or two are about the only thing that you must plunk >down $$$ for if you are serious about coiling. I paid $150.00 >each for mine, and never looked back. If I see another you can be >sure I will plunk $150-$200 again without batting an eye. The >price for new Powerstats would curl your hair and loosen teeth. I looked at the price for a 15 Amp unit and my hair curled at that… RQ>Now do you want to be sick? I was out in Richmond Virgina last >summer visiting some coiling friends. They have a scrap yard >there that would… well I can't use that language here. Anyway, >six 45 amp Powerstats in NEW condition, complete with remote >drive (geared, motor driven common shaft with remote unit)… >Price… RQ>$45.00 for the whole load, and the springs on his van were Hey Richard… Thanks a *lot* <grin> Just what I wanted to hear… There are a couple of technological junk yards here too but the people running them have an inflated idea of what the stuff is worth. Three of them have gone out of business in the last few years so maybe they are willing to listen to reason… ( They will check a current catalog price and then sell the surplus goods for 50% of that cost… Gimme a break! ) RQ> DH> Also, I just sent the application off to Harry Goldman for > DH> the TCBA membership. RQ>Welcome aboard! If you told him I sent you then I get a free >issue of the NEWS at no cost to either of us!!! Thanks! I sure did! Anyway, I will talk with you later - Dave -!- b QMPro 1.51 b Windows 3.1 - The colorful clown suit for DOS… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1904 Date: 12-16-93 11:13 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil 1/2 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> Sometime in the next month or so, I will have to go through > DH> and copy some other issues. They do an occasional > DH> "History of Electronics" article. Fun stuff! RQ>I would be interested in seeing more stuff like this if it >catches your eye. I will do that - I keep some of the back issues. RQ>Referring to Tesla: RQ> RQ>He was THE electrical genius of his time. RQ> DH> I also think C. P. Steinmetz was an interesting character > DH> but Tesla was way ahead of everyone. RQ>Steinmetz was by no means a slacker. He gave us a lot in his area >of expertise. But when it came to bulk technique, research, and >knowledge; Tesla was a head and shoulders above the crowd. >(literally and figuratively) This is true! My favorite Stienmetz story was that he could never get the hang of driving. He was always running the car up onto peoples lawns, into other cars, etc… He had a car customized with a second set of controls in the trunk and he had someone sitting there, looking through a periscope and doing the actual driving while he would serenely cruise through the neighborhood, hand on the wheel, smoking a cigar… Fun stuff… RQ>Tesla's genius spanned an important era in mankinds history. His >foresight ranks with Da Vinci, and his technical abilities were >second to none. He intellect was broad, where others were very >narrow and focused. This is what I gathered too - I also heard about the remote control vehicles he built - the submersible boat ( no antennas either ) RQ>Tesla was a mechanical engineer, an electrical engineer, a radio >engineer, and a visionary. I have seen credits that he was a >funds to pay for a higher education. Yet he handed (hand drawn) >plans for the first AC induction motor to a shop foreman for >construction. The motor worked perfectly without modification or >adjustments, and the exact same design is still used today. >Without missing a step he went on to design three, then four, >then six phase motors. Along the way he designed the power grid >to supply them. Yeah - I heard that he was sitting on a bench somewhere and the motor came into his head completely formed. Just sitting there in his imagination, running smoothly… RQ>He did this not once in one area, but hundreds and hundreds of >bladeless turbines and pumps, viscosity speedometers, electrical I know about the turbines - a flat disk, no cups or anything - high speed and very efficient… RQ>I will forgive him that his overactive imagination led him to >believe he was recieving signals from mars, especially since the >nearest pulsar is many light years further away, the signal is >exceedingly weak, and radio had not been invented yet (by >Marconi). Interesting - kinda pre-dates Janssky ( sp? ) by a few years… RQ>I could go on. The bottom line is the other famous names of the >era were good, but they were narrow and clumsy compared to the >light that Tesla threw. RQ>Someone mentioned a book from Barnes and Nobel: The Inventions >Writings, and Research of Nickola Tesla. In the lectures >published in the book, Tesla demonstrates a single terminal bulb >with a brush discharge (1891). The book shows photos of this and Interesting - I'll have to look for it. I just picked up a copy of a 1904 reprint: Experiments with Alternate Currents of High Potential and High Frequency - the text of a lecture he gave at the Institution of Electrical Engineers in London. There is also an appendix: Transmission of Electric Energy without Wires. The book is published by Angriff Press, P.O. Box 2726, Hollywood, CA 90078 ISBN# 913022-25-X The book details a lot of the electrical discharge lights. From the text of the book it sounds like he was quite an energetic lecturer too.. I know where *I* want to set the time machine! Anyway, I will be going away for two weeks, getting back on the first. If I do not talk with you before then, have a great holiday! TTYL - Dave ë:-) -!- b QMPro 1.51 b Money has proved the most dangerous of hallucinogens. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 16 Dec 93 17:35:00 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Again referring to Tesla: DH> Yeah - I heard that he was sitting on a bench somewhere and DH> the motor came into his head completely formed. Just DH> sitting there in his imagination, running smoothly… This is apparently true, Tesla told the story on more than one occasion. Many other notables of genius status have said their greatest ideas came in similar fashion, or in dreams; but few were as prolific as Tesla. It seems that ideas like this came to him very frequently over a number of years. He complained more than once that it was simply impossible for him to act on all of them. Tesla read Edison's quip that invention was "1% inspriation and 99% perspiration" and remarked that the inverse was in fact the truth. He stated that he was able to operate sophisticated mechanical and electrical devices in his head to determine feasibility prior to drawing or constructing the actual device. He followed this statement up by saying that he never built a device that did not operate as anticipated. In his later years, after failing to fund the Wardenclyff transmitter to completion, he was unable to maintain a laboratory. He did not stop inventing however. He set his MIND to work building, testing, and operating equipment. The result of his purely mental efforts were designs for such devices as particle beam weapons. This mental work came into tangible existence in the form of drawings for such components as the open ended vacuum tube (one end open to STP) for generating high energy particle beams. It is one of the true crimes against humanity that he was so misunderstood that even a small lab could not be furnished to allow him practical creative outlets, though much blame may be laid to him for his ignorance of financial affairs, and his refusal to retain a business manager to see to those affairs. He spent money like water, money having no real value to him. He allowed people to purchase valuable patents outright instead of insisting on long term royalty agreements in addition to the lump sum payments, which would have insured some future income. Had he been monetarily wiser, he would not have died penniless, and many more ideas could have seen commercial application; even if the final marketing was done by others. Have a good vacation, I look foward to hearing from you upon your return. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2006 Date: 12-17-93 20:35 From: Ron Lawrence To: Dave Halliday Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ > BC>Do you connect the neon sign transformers in series or what? > > A combination - the transformers are 12kV at 30mA so I will > get 24kV at > 60mA by using four of them. I'd be REALLY cautious about paralleling ANY non-precision transformers, and on neon light transformers, watch out for there being an internal, tied to case, center tap - lots of 'em are built that way. I about fried myself in junior high school due that grounded center tap! (When ya stack two in series for more volts, you can, and often do, get a massive flash-over to the AC input, and that 600v insulation just isn't adequate to keep it from further jumps!) …RON… -!- Opus-CBCS 1.73a ! Origin: C C I B B S (509)663-8397 (1:344/58.0) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1947 Date: 12-18-93 01:15 From: Richard Quick To: Patrick Kirol Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ PK> Richard I have been following your coiling discussions here PK> for some time and would like to get a copy of the video tape PK> you have and a copy of the Tesla coil information you posted PK> on this echo. I would also like to get your advice on which PK> coiling program you would recommend. I have noticed that PK> there are a couple different ones out there. I am mailing PK> out a tape and disk (and check) today. You will love the tape if you are the slightest bit interested in coiling or other high voltage equipment. I run some hot stuff here. I will get your copy out within 48 hours of receipt of your package, but please allow a few extra days due to the holiday mails. As for the coiling program I would recommend you purchase THE TESLA COIL DESIGNER by Walt Noon. This software is sold through several publishers and book dealers, but I can't find a catalog handy. However Walt would love to hear from you, and please tell him I provided you with his address (I owe him a letter). Walt Noon 3283 Belvedere Riverside, CA 92507 The software is pretty good but I really only use it for one purpose: it enables me to determine within tollerable limits the inductance and resonate frequency of the secondary coil, and the tank circuit frequency. Used intelligently this menu driven software will take simple U.S. physical measurements from a planned design and give you real working numbers as to operational frequency of the system, rough tuning, number of primary turns required, and the size of the capacitance and power supply needed. This will cut the hours and hours of time required with a calculator and book of tables and formulas… down to seconds. All of the required tables such as dielectric constants, line frequencies, toroid capacitances, etc. are already in the software. It is really just a matter of plug and chug. The functions it covers includes nearly every major componet of the 1/4 wave Tesla coil; having calculators built in for capacitors, power supplies, tank circuit frequencies, discharge terminals, etc.. The only thing I will have to fault is the spark length calulator that the program uses, I frequently blow the programs estimated maximum disharge length away on my real systems. Walt tells me it is not the program, but the coiler (me) who is at fault. <BIG grin> Combined with the practical information presented on the video tape, copies of this thread, and some of my spark gap designs I will include on the disk, you will have a wealth of accurate coiling information. As always, I am available here to answer questions, offer advice, and can trouble shoot any problems you may encounter. Good Luck!!! -!- … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2000 Date: 12-18-93 23:44 From: Robert Holtz To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Well, After reading whats been going on in the conference between yourself and the other members I'm pleased to see a dialog develop. Thank for letting me know it was productive >;-) -!- b QMPro 1.51 b From small chips to big breasts, silicone is the best ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2145 Date: 12-19-93 11:08 From: Robert Taylor To: Richard Quick Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ Quoting Richard Quick to Robert Taylor ⇐- RQ> Yes I did. I take it then you missed my reply. Looks like you're right. I think the BBS that I picked you up on was having some problems around that time, so end of mystery. RQ> I own a copy, and a copy of nearly everything else worthy of RQ> note on the subject. Guess I shoulda known better on that one! You must have one heckuva Tesla library. RQ> intended to become public. This private material, when RQ> combined with his patents and patent applications, reveals RQ> much larger plans. I can only imagine how interesting some of this material must be. I was aware of some Hungarian translation of his private papers was out there, but have never seen a copy of same. Just out of curiosity, are you familiar with anything regarding Tesla's connection with the "project invisibility" & the U.S.S. Eldridge? Ran across something that connected him with the project, but everything that I've seen is vague. An impression was left that he may have had something to do with the building of the alleged field-generator. BTW–did catch your reply on my post about Ken Strickfadden. His work always amazed me. Seasons Greetings & Happy Holidays. … C:\\DOS C:\\DOS\\RUN RUN\\DOS\\RUN WATCH\\DOS\\CRASH ! Origin: BLUFF CITY BBS (1:123/70) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2 Date: 20 Dec 93 01:30:00 From: Richard Quick To: Brian Carling Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ BC> Yes, unfortunately I missed many of the earlier posts… BC> what is the capacitor for? What is it like? Capacitance is required in the tank circuit to convert line frequency power into RF (radio frequency) pulses. It works like this: A capacitor designed to discharge in a pulse, and able to withstand high voltage, is charged with the power supply xfrmr. The power supply xfrmr usually puts out a high voltage (6-20kv). Since you are stepping up your line voltage (120/240) with a transformer, your output current gets smaller as the output voltage gets higher. So if you are using neon sign xfrmrs, say 12,000 volt 30 millamp output units, your input current is high, say 3 amps (if the transformer is power factor corrected). Your output is a measly .03 amps. Not much power here, only 360 watts. But if you take that .03 amps (@12kv) and charge up a capacitor with it, how many watts will you get if you discharge the capacitor? That will depend on how fast you drain the cap. Lets say you short the cap out and pulse discharge it. Currents in the order of a few dozen amps are easily obtained this way. Now if you match the size of the capacitor to the amount of energy produced by the HV power supply in 1/2 of a 60 cycle wave (the + polarity, then the - polarity) you will be able to fully charge the cap in 1/2 cycle. In the common case with a power supply at 60 cycle, then you can fully charge the cap 120 times per second. Instead of just shorting the cap out with a wire or buss bar, let's discharge the cap through a heavy, low impedance coil. In order to properly time the discharge so that the cap fires only when fully charged, we need some type of high voltage switch. The switch commonly used is an air gap, or spark gap. When the capacitor is charging it is receiving energy, as it recieves energy there is current flow from the power supply. The more cuurent flowing, the more depressed the circuit voltage becomes. This is voltage drop, the input energy is limited, the current is high, so the voltage must be low. As the capacitor charges the voltage rises, until there is no more current flow. When current stops flowing into the cap (fully charged), the voltage peaks, and the spark jumps the gap. This spark (arc actually) discharges the capacitor very quickly. Once the energy of the discharge is used, the spark gap opens up, and the capacitor is free again to recharge from the power supply. One interesting property of capacitive discharge through a conductor is oscillation. During the discharging of a capacitor in a circuit such as this the pulse of energy actually swings back and forth from one capacitor plate to another until the energy is consumed. The frequency of oscillation changes according to the size of the capacitor, and the length of the conductor. Large capacitors slow the frequency of oscillation, as due long conductors. The frequency of a typical Tesla tank circuit (capacitor & heavy coil) typically range from 1 mHz on the high end to say 20-30 kHz on the low end. The peak currents and voltage seen in the heavy primary coil are a function of the capacitor and power supply. The circuit is designed to deliver a maximum of voltage and current over a very short period of time. Peak powers in this circuit may reach many megawatts with relative ease, due to the capacitve discharge. -!- … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2102 Date: 12-20-93 01:42 From: Richard Quick To: Patrick Kirol Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Patrick, I got your Tesla video tape request in the mail today. The archives, GIF schematics, and many pages of notes are on the disk. The tape is full up. I will return mail the tape and disk first thing tomorrow. Good luck, and if you get a coil up and running please tell us about it. As I have stated here before: if you have any questions or comments about the video, please feel free to post here. I would love to hear from you. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2103 Date: 12-20-93 03:24 From: Richard Quick To: Ron Lawrence Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ > BC>Do you connect the neon sign transformers in series or > what? > A combination - the transformers are 12kV at 30mA so I will > get 24kV at 60mA by using four of them. RL> I'd be REALLY cautious about paralleling ANY non-precision RL> transformers. Running these xfrmrs in parallel is really no problem at all. I do it all the time on really LARGE banked power supplies (over 4 killowatts from 360 watt neons) and have never had a problem. Good high voltage technique requires some bypassing caps, and a safety spark gap with center tap ground to protect the power supply from kickback, flashover, burnout, etc.. With a little technique a parallel bank will hold up quite a while without failure. Even without much protection beyond a safety gap, they will still hold up for hours of high voltage fun. The ease in paralleling these particular type xfrmrs is from the magnetic leakage core shunts. The internal shunting is very forgiving to load imbalances. I posted both Dave and Brian about attempting to run these units with the secondaries in series. This could be a bad scene if one of the secondaries were to open, and the case and core were to pick up 6 kv or so. -!- … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2101 Date: 12-20-93 09:30 From: Robert Holtz To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ → As our local co-sysop, and an eyewitness to both some of my → working systems, and the video records, would you care to state → an opinion? I know you too have shown some of the video to → others. Any comments? A far as stating an opinion goes I'd say it's impressive to say the least. Since I have only seen one machine spewing forth 15 foot lightning bolts is hard to do a comparison. When showing the tape to other people it's hard to convince them that someone is actully doing this in their basement somewhere in the suburbs. :-) cya ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2148 Date: 12-21-93 14:03 From: Richard Quick To: Robert Taylor Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Regarding: The Inventions, Writing, and Research of Nickola Tesla available from Barnes & Noble Booksellers RQ> I own a copy, and a copy of nearly everything else worthy of RQ> note on the subject. RT> Guess I shoulda known better on that one! You must have one RT> heckuva Tesla library. Over 200 separate covers at this time. A lot of the material I have read two, three, even four times looking for clues. RT> I can only imagine how interesting some of this material RT> must be. I was aware of some Hungarian translation of his RT> private papers was out there, but have never seen a copy of RT> same. I believe the book you are referring to is the Colorado Springs Notes, which were hand written in english in 1899-1900. These papers and many others were processed by the Office of Alien Affairs at the time of Telsa's death (though he was a full citizen…). Telsa had no relatives in this country. Before his death the Yugoslavian government had declared him a national hero (while we were busy starving him). When the Yugoslavs found that he was completely destitute, they set up a trust fund to see that he received a monthly check to cover his food and rent. It was all he had when he died. Since the Yugoslavian government was taking responsibility for his care, the U.S. government declared Yugoslavia the next of kin. The personal effects found in his hotel room were pilfered (many valuable items were stolen), and what remained were sent to Belgrade where they were placed in a museum. In the mid 1970's the curator of the Telsa Museum in Belgrade cataloged all of the papers written by Tesla in Colorado Springs. About this time "pilgrams" such as Robert Golka began showing up at the museum to read the originals. The curator decided to publish through NOLIT of Belgrade, and copies were made available in the U.S. for around $45.00 for a beautiful gold leaf, leather bound edition. Today my copy is worth over $100.00. The book has reprints of most of the surviving photos Tesla took of the lab, it's contents, and some of the experiments performed there. It should be noted that Tesla was very proud of his U.S. Citizenship. He spoke five languages fluently, but english was his mother tongue. All of his patents, articles, and interviews were conducted in english, and all of his notes were in english. RT> Just out of curiosity, are you familiar with anything RT> regarding Tesla's connection with the "project invisibility" RT> & the U.S.S. Eldridge? Ran across something that connected RT> him with the project, but everything that I've seen is RT> vague. An impression was left that he may have had something RT> to do with the building of the alleged field-generator. This area would most definately fall under the protection of National Security interests, and as such would be highly classified if the project did in fact take place. I have never seen any concrete proof of this project or Tesla's involvement. But that does not stop the stories and conspiracy theorys. I have heard more than a few. I cannot say if any of this is worthy of believing or not, as I base my information on facts not hearsay. Nobody to my knowledge has presented verifiable facts on this. But it is a fact that to this day the U.S. government has a Top Secret classified archive in Washington D.C. which contains the bulk of papers Tesla wrote in his later years. Some of these papers are believed to have orginated from his hotel room, but the bulk of these papers (many boxes) were removed by the Office of Alien Affairs from his rented storage room. They were not turned over to the Yugoslavian government because they were not considered to be "personal effects". It is my understanding that these papers concern Tesla's particle beam weapon plans, and more likely than not the field generator plans if they do exist. As I have stated, the existence of the archive has been established, as well as the fact that many unpublished documents written by Tesla reside there. The exact catalog of documents is a mystery. It is interesting to note that 50 years after Tesla's death, the U.S. government still considers these documents to be of the gravest concern to national security. Related filings under the Freedom of Information act has revealed clues on some of these documents. It is a known fact that the powerhead design for a coil driven particle beam weapon resides there. This powerhead was a vacuum tube open to the air at one end. Vacuum was maintained at one end of the tube by using a vortex of compressed air, so the tube geometries are similar to an aspirator pump. The tube contained a standard capacitive discharge rail gun at the low pressure end which produced and accelerated metal plasma. The main system energy was given to the plasma from a large Magnifier system (believed) which provided voltage to further accelerate the plasma to near light speeds over a very short distance. I have seen reproductions of original unpublished sketches that Tesla made of this powerhead that were included with his papers sent to Belgrade, and brought to light by one of the "pilgrams" returning in the late 1970's. I have no doubt as to the the authenticity of the information I saw, as there was a representive of the museum in attendance when the sketches were viewed and discussed, and the reproduction bore the identical museum authenticity stamp that my published copy of the Colorado Springs Notes bears. Back to your subject of "project invisiblity", I have heard nothing but rumors. I heard a guy a couple of years back who claimed to have seen Tesla at White Sands early in the war working on a classified military project. This story could not be verified, and the teller offered no proof. Good story though. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2431 Date: 12-28-93 05:56 From: Patrick Kirol To: Richard Quick Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ Quoting Richard Quick to Patrick Kirol ⇐- RQ> In case you missed my post yesterday that included information on the coiling software that you inquired about earlier here is a brief recap: RQ> Tesla Book Company, P.O. Box 121873, Chula Vista, CA. RQ> 91912. They have a 1-800-398-2056 information, catalog, and RQ> ordering service. Richard, I received your tape and disk today in the mail,… WOW that thing packs a wallop! Makes me want to go out and get to work on building a couple of your caps and getting things cracking! You could work out the rough edges and turn it into a "how to" film or maby a "school demonstration" film for HS/College level physics classes. Have you received any requests for coils to power other devices, lasers etc.? I realy think you should package the tape and some instructions into a how to thing for beginners. I was wondering about the shape/path that the sparks take esp the ground strikes. Are they in some way an expression of the way the charge is stacked up on the secondary? When you run the coil outside does wind have any effect on where the coil strikes? I realize from your discussion that my coil lacked so many things, notably a regulated power input, adequate tank circut, grounding, dimensions I had about 70 ft #10 coper wire as a primary, 1500 feet of secondary on a 2.5 inch pipe (that stood too tall from the primary). I had no way to measure if I was getting anything off the secondary, the neon lights were a good idea. I will read through your disk files and try again. Thanks for your time. My dad would have loved your garage setup. Don't melt any nails! Pat Kirol (also on the net Patrick Kirol@lambada.oit.unc.edu) ` -!- Blue Wave/Max v2.12 ! Origin: The Federal Post -{*}- Spring-Lake, NC (1:3634/2) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 28 Dec 93 12:51:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Well I hope everyone had a happy holiday. I am now recovered enough to post some more specific info on Magnifier construction and operation. I have covered some general material on this revolutionary Tesla coil system, but will now endeavor to throw out some specific pointers for those of you who have an interest in this much more efficient RF power processor. As I have mentioned the Magnifier is a three coil system. The primary is excited from a Tesla tank circuit, the secondary coil is inductively coupled to the primary, and the extra coil is top loaded on the secondary in such a fashion as to be uncoupled completely from the primary/secondary "driver" coils. The extra coil is base fed by transmission line, which can be anything from Litz wire, copper pipe, or heavy DC transmission wire. The keys to getting an efficient Magnifier setup in operation can be listed fairly easily: Close coupling between primary and secondary, good gap quenching, and proper impedances in the secondary driver and the extra coil. Coupling in Tesla magnifiers must be tight. Classic style vertical helix primaries are very practical for use in Magnifier systems, but heavy insulation between the coils must be used to prevent flashover. The close coupling reduces somewhat the VSWR in the driver secondary, and the 1/8th wave output contains substantially less voltage than a normal 1/4 wave Tesla system, but the close physical proximity between coils means flashover will be a problem. Use several layers of polyethylene plastic around the secondary, and insulate the top primary turns with heavy vinyl hose. It has come to my attention that tapping the primary coil from the bottom turns, and heavily insulating the top turns, reduces flashover. (now gee, why didn't I think of that?) Good gap quenching is a must. Because the coupling is so much tighter in Magnifier systems, more strain is put on the main system spark gap. If ever there was a need for exotic spark gap systems this is it. Quench times must be low, low, low, in order to trap the maximum energy into the secondary driver. An un- quenched (closed) gap will allow energy in the secondary back into the primary/tank circuit. This must be prevented. In Colorado Springs, Tesla used a pair of air blast gaps in series with a massive rotary. He kept pushing his line frequency higher (he had a massive, variable speed alternator in the lab), increased his break rate (up to 50,000 bps) and kept the energy delivered per pulse down to a minimum. The reason he strove to keep the energy per break down was to prevent overloading his gaps. As energy per break (voltage * current) increases, quench times decrease and efficiency in the Magnifier drop off. The increase in the number of breaks per second allowed the total energy processed to climb to unheard of levels, with unheard of performance and efficiency. The next key point to building and operating a small to medium Tesla Magnifier is proper coil impedances in the secondary driver and extra coil. The extra coil must have a higher impedance than the secondary driver. The extra coil must be lower in resonate frequency. I have mentioned here that the 1/8th harmonic output of the secondary driver coil matching the natural 1/4 wave resonate frequency of the extra coil is the most efficient mode of Magnifier operation. This is true, but don't get bogged down with it. This system will work and fire (within reasonable limits) with any extra coil that has a higher impedance and inductance that the driver secondary. Let me give some tips. I have found that most high performance 1/4 wave secondary coils make lousy driver secondary coils in the Tesla Magnifier. The reason is the impedance and inductance are too high, and the 1/4 wave coil is not designed or constructed to handle high current outputs. 1/4 wave coils built per my instructions (posted here several times) are designed to produce excellent 1/4 wave voltage peaks, not 1/8th wave current. Your best bet is to wind a special coil for use as a driver. With this in mind what type of coil design would work best? Well my first decent driver coil was built for use as a 1/4 wave resonator, but it dropped into the role of a Magnifier driver without complaint; it had a a nice low aspect ratio, and it was wound with heavy stranded wire… A good general purpose Magnifier secondary has a very low aspect ratio for good tight coupling over the entire winding length (say about 1.5:1). It is wound with heavy stranded insulated wire (say #18 or larger) to help carry heavy RF currents with lower losses. The frequency of the coil should not be too low, say in the area of 400 kHz for most medium systems. For the extra coil you want to pack a lot of inductance into a small unit volume, but not too much. You will end up with an amazingly short resonating coil if this is done properly. Use a 6" or 8" coil form with an aspect ratio a little over 2:1. For winding the coil use say #20 -#24 double Formvar magnet wire. The extra coil must be heavily top loaded with toroid discharger in order to produce really killer performance, as is the case when pumping a lot of energy through any magnet wire coil. The impedance in the bare extra coil must be higher than the driver coil by some margin, and the frequency of the extra coil should be brought down around 200 kHz by top loading the coil with discharger. The impedance of the driver must be low (heavy stranded wire spaced by insulation) while the impedance of the extra coil must be high (thin magnet wire, close wound turns) The tank circuit of the Magnifier must be tuned to the same frequency as the extra coil with discharger. Set the driver secondary inside the primary and run a transmission line some 6- 8' to the extra coil. The extra coil must be away from any field damping effects such as ground, large metal objects, other coils etc. It must be allowed to resonate as freely as possible. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2 Date: 30 Dec 93 11:08:24 From: Richard Quick To: Patrick Kirol Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ PK> Richard, I received your tape and disk today in the mail,… PK> WOW that thing packs a wallop! Nobody who has seen the video will argue with you. Peak powers of 22 megawatts in a spark discharge look VERY impressive. Nobody who has sent for the tape has asked for their $10.00 back either. <grin> PK> Makes me want to go out and get to work on building a couple PK> of your caps and getting things cracking! Go for it! PK> Have you received any requests for coils to power other PK> devices, lasers etc.? Very few people out there believe it can be done, and even fewer are doing ANY research at all into these areas. One of the problems with the standard 1/4 wave systems featured on your copy of the video is that the impedance of the output is too high for powering lasers etc. directly. However the Tesla Magnifier circuit offers the means to increase the processing efficiency, decrease the impedance, and generate still greater peak powers. This is the direction the research must go. PK> I realy think you should package the tape and some PK> instructions into a how to thing for beginners. I have thought about it, but as of yet have not done anything in this direction. The tape clearly shows it CAN be done, and I have been surprised with the number of respondents who built coils but could not get spark. With the information on the tape, the archives from this thread, and my availability here to answer questions, it should be possible to get a foot up into this very interesting (and neglected) area of RF power processing. PK> I was wondering about the shape/path that the sparks take PK> esp the ground strikes. Are they in some way an PK> expression of the way the charge is stacked up on the PK> secondary? I assume you are talking about strikes from the discharge terminal to the strike rail protecting the primary coil. The frequency of strikes to the grounded rail was partly my fault. The toroid discharge terminal needs to be lifted higher off the secondary as the diameter of the toroid grows. The last few runs show the coil operating with the toroid at less than optimium height. Had it been set higher the spark would tend to strike the ground rail less. The spark is caught up in the field flux interaction between primary and secondary and is following the lines of magnetic force in this field. Once they get away from the field however I assume they are pretty much random, hitting everything within striking distance, which is at least 11 feet in this instance. PK> When you run the coil outside does wind have any effect on PK> where the coil strikes? Most definately. Weather conditions outside bear a lot on the coil performance. Wind will blow sparks all over, and will cause the system tune to vary. A corona cloud forms around the toroid as a result of the megavoltages present. With discharge present you cannot see this with the naked eye or on video, but time still photography will show the cloud clearly present. The effect is very pronounced when using small toriods at high power. This corona cloud affects the system by acting as a larger discharger, increasing the capacity of the toroid, and lowering the resonate frequency of the secondary. When wind blows it removes the ions, and the secondary tune seems to jump up and down with the gusts. I have had circuit failures that I believe were caused by this wild, wind induced, frequency changes, but my eyes never saw anything like the spark writhing around in the wind. PK> I realize from your discussion that my coil lacked so many PK> things, notably a regulated power input, adequate tank PK> circut, grounding, dimensions I had about 70 ft #10 coper PK> wire as a primary, 1500 feet of secondary on a 2.5 inch pipe PK> (that stood too tall from the primary). I had no way to PK> measure if I was getting anything off the secondary, the PK> neon lights were a good idea. I will read through your disk PK> files and try again. Thanks for your time. My dad would PK> have loved your garage setup. Don't melt any nails! Well it should be pretty clear now, and you have the most up to date and comprehensive information on 1/4 wave Telsa coils available anywhere to the best of my knowledge. Take your time and look over all of the text files I sent, look at the spark gap schematics, look at the video. I have hidden nothing; it's all there. If you have any questions or comments just post me, I will be more than happy to answer. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 30 Dec 93 16:41:00 From: Richard Quick To: All Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ For the beginner: The best sized coil system for those of you who are interested in building your first really "hot" Tesla coil is based on a 6" diameter secondary coil. A coil this size runs very well at 1500 watts and can be driven to 2000 watts without much problem. Spark lengths of 55-60" can be easily obtained with such a coil. The parts for a unit like this can typically be accumulated for around $150.00 as I have posted before. Figure your designing and construction time will run from 40 to 80 hours depending on the shop facilities available. Most people who build a coil do not go on to design and build a second unit. The reason for this being that the first effort more often than not fails to work as the designer/builder had hoped, and the project gets relegated to a dusty corner somewhere. I lay blame for this on coil plans and designs advertized, published, or sold in the last 20 years that were based on plans and designs popularized in the 1920s and 30s. These plans made use of what I call "classic" coil componets, which includes: long skinny secondary coils with space wound or insulated wire windings, plate glass capacitors, solid copper wire primaries, needle type spark gaps, and small sphere or knob type dischargers. "Classic" coils of this type are miserable performers frequently using unsafe tank circuits and grounding techniques. The prevalence of these coil designs persists to the present day and are responsible for many a budding coiler to quit in disgust after getting nothing but a nasty shock or two from what was advertized as a clean RF spark output from the secondary. That is if they got even that. My first coil was a huge effort to build while I was in high school. The plans for the coil came mail order from a company that advertized in the back of Popular Science some years back, and was plagued with every possible design fault I listed above. I never was able to get a single spark from the discharge terminal. I thought "performance" Tesla coils were nothing but a myth, and felt I had been taken in by a dream. Years later I bought another set of plans, and had similar results. But I associated myself with a group of people who were intent on bringing the 1/4 wave Tesla coil and the Tesla Magnifier out of the pages of history and into current practice. As a result of many many hours winding coils, building capacitors, and researching Tesla's original notes, I am happy to report sucess in bringing the Tesla coil into the 1990s. It is efficient, inexpensive, and capable of enormous peak powers off the discharge terminal. The modern design "reinvented" by trial and error is a very worthwhile project for anyone interested in high voltage or high energy RF. Since October I have been posting information and answering questions regarding coiling, and the modern designs that we have evolved from Tesla's original work. I have recieved many positive responses from regulars in this conference regarding my work, and have done my best to "set the record straight" regarding Nickola Tesla and his place in history. Much of the information regarding the coils themselves has appeared in print here for the first time, and my posts have added up to over 100 pages on this subject. So I guess what I am saying is: If you have built a coil, or you are thinking about building a coil, grab the archives from this thread. If you can't build a really hot coil system from the information that has been released here, you never will. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3 Date: 03 Jan 94 13:31:24 From: Richard Quick To: Damian Wright Subj: Re: big magnetic pulse ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JA> I'd like some ideas on generating a LARGE magnetic pulse or JA> field. DW> This'll create a magnetic pulse, don't know how big though, DW> it's a Tesla coil, (with lots of copper wire), it's not too DW> dangerous, it only kicks out about 40000Volts, but at a DW> pretty low A of course, if you're interested drop me a line DW> and I'll post the article I read on it up here on this net. I have been posting on high powered Tesla systems in this conference for some time. The Tesla Tank circuit is the pulse field generator. It uses a spark gap switch to pulse discharge a HV cap through a large coil. The EMFs produced are incredible as peak powers in this circuit can easily reach many megawatts. My largest Tesla system has peak powers of 22+ megawatts and will light florescent bulbs at 50-60' without any wire connections to the tube. It will erase bank and credit card magnetic strips at a few yards, and is lethal to digital circuits (watches, calulators, etc.) at a similar range. You do not need a secondary resonating coil (Tesla coil) inductively coupled to the tank circuit, the tank circuit is actually more effective alone than when coupled to the secondary resonator. I have a two hour video tape that shows the basic setup and operation of several of these systems. The video has shots showing gas discharge bulbs lighting at several feet away from systems that were tuned to produce sparks, not pulse fields. Modification to a system such as you desire would be very minimal. These systems BTW are designed and built for continous duty operation. Even though the caps are pulse discharged, and the peak powers are very high, the system produces more or less a continous field. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 4 Date: 03 Jan 94 13:49:37 From: Richard Quick To: Damian Wright Subj: Re: big magnetic pulse ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JA> I'd like some ideas on generating a LARGE magnetic pulse or JA> field. DW> This'll create a magnetic pulse, don't know how big though, DW> it's a Tesla coil, (with lots of copper wire), it's not too DW> dangerous, it only kicks out about 40000Volts, but at a DW> pretty low A of course, if you're interested drop me a line DW> and I'll post the article I read on it up here on this net. I'd beg to differ on a point or two. First you are correct in pointing to Tesla systems as a potent source of EMFs. The primary coil/tank circuit produce the EM fields in question. But the HV producing secondary would not be required, or even desired, if maximum field strength are all that is wanted. In addition, the secondary coils are quite capable of producing voltages in the megavolt range even with coils as small as 6" diameter and 2' tall. My larger 10" diameter, 32" high secondary produces between 3-5 megavolts with ease and is capable of 11' discharges (common) with recorded discharges up to (and even exceeding) 15' in length. Low amps? NOT! These bolts come off as thick as the average mans leg. Running the large system with 10 kVA 60 cycle input I get peak powers of 22 megawatts average; with an output voltage of 5 megas this works out to over 4 amps current at the discharge terminal. While this may seem low, the system was designed to produce a null current 1/4 wave voltage peak on the discharger, and my figures are all conservative. Should I choose to alter the design parameters and shoot for a higher current output I see no reason why lower voltages at currents in excess of 1000 amps could not be produced. … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2581 Date: 01-03-94 13:53 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Hi Richard - just got back a couple days ago. Great trip! Anyway, I'll be starting the actual construction of the capacitors and the coil in the next week and will keep you posted! I am going to be near Boeing Surplus tomorrow and if the high-voltage DC supply with the nice 39 Amp Powerstats is still there I'll offer 'em a hundred bucks for it and see what happens! ANyway, I will keep you posted as to what is happening and will be keeping the tape rolling all throughout the testing process. TTYL - Dave -!- b QMPro 1.51 b Live long and phosphor… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2577 Date: 01-03-94 13:59 From: Richard Quick To: Jim Arconati Subj: big magnetic pulse ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JA> I'd like some ideas on generating a LARGE magnetic pulse or JA> field. DW> This'll create a magnetic pulse, don't know how big though, DW> it's a Tesla coil, (with lots of copper wire), it's not too DW> dangerous, it only kicks out about 40000Volts, but at a DW> pretty low A of course, if you're interested drop me a line DW> and I'll post the article I read on it up here on this net. I have been posting on high powered Tesla systems in this conference for some time. See the thread: 10KVA Tesla Coil The Tesla Tank circuit is the pulse field generator. It uses a spark gap switch to pulse discharge a HV cap through a large coil. The EMFs produced are incredible as peak powers in this circuit can easily reach many megawatts. My largest Tesla system has peak powers of 22+ megawatts and will light florescent bulbs at 50-60' without any wire connections to the tube. It will erase bank and credit card magnetic strips at a few yards, and is lethal to digital circuits (watches, calulators, etc.) at a similar range. You do not need a secondary resonating coil (Tesla coil) inductively coupled to the tank circuit, the tank circuit is actually more effective alone than when coupled to the secondary resonator. I have a two hour video tape that shows the basic setup and operation of several of these systems. The video has shots showing gas discharge bulbs lighting at several feet away from systems that were tuned to produce sparks, not pulse fields. Modification to a system such as you desire would be very minimal. These systems BTW are designed and built for continous duty operation. Even though the caps are pulse discharged, and the peak powers are very high, the system produces more or less a continous field. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2584 Date: 01-03-94 15:39 From: Dave Halliday To: Jim Arconati Subj: Big Magnetic Pulse ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ JA>I'd like some ideas on generating a LARGE magnetic pulse or field. >Yeah, I know… "just set off a low-yield nuclear weapon," etc, etc… JA>Save the bandwidth – I want practical ideas (or non-nutcase theory) >on generating strong magnetic fields. How Big? Well how big can >I make one (without the nuclear device)? What's the strongest magnetic >field, and/or biggest magnetic pulse I could make without esoteric >devices (super-cooled superconductors are included in my definition >of esoteric.) You can make a really large magnetic field but how large of an area do you want this field to be in… That is where you get into hideous amounts of input power. Your best bet would be to have a large capacitor bank, charge it up to a couple tens of KV and then use some kind of flash discharge to connect it to your magnetic coil. Only problem would be the highly lethal voltage and current - not something to get into casually. TTYL - Dave -!- b QMPro 1.51 b Multitasking = screwing up several things at once. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2579 Date: 01-03-94 17:07 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Dave, I saw a post of yours up on the net today and thought I would drop you a line. How was your vacation? I am interested is following up on your coiling activities, and wanted to tell you that another conference regular has received a copy of my tape and is going to be jumping back into coils after problems with his first unit (failed to produce the promised results). I sent him all of my notes, the plans for the spark gaps and the thread archives. I know with this information he will get the results he is looking for, but it will probably take a week for him to read through all of the material I have sent. On another note I have seen a post from Jim Arconati wanting information on strong EM field generators. I tried to drop the hint that the Tesla Tank circuit is the only way to go if you want maximum peak powers. No other circuit I have seen or worked with can produce rapid, megawatt range, pulses. I hope you can find the time to get your cap, coil, and tank circuit together in the next couple of months. I really am looking forward to getting some video and/or photos of your work in the near future. Good luck, and remember to "Tune for Maximum Smoke!" … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2580 Date: 01-03-94 17:21 From: Richard Quick To: Damian Wright Subj: Re: big magnetic pulse ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DW> This'll create a magnetic pulse, don't know how big though, DW> it's a Tesla coil, (with lots of copper wire), it's not too DW> dangerous, it only kicks out about 40000Volts, but at a DW> pretty low A of course, if you're interested drop me a line DW> and I'll post the article I read on it up here on this net. P.S. I am interested in seeing the article if it would not be too much trouble to peck it out. The 10KVA Tesla Coil thread has more than a few followers who would also appreciate seeing the material. I will apologize in advance for critiquing the material (and your reply earlier) but I have seen too much misinformation published and repeated on this subject. I have built more than a few high power Tesla systems, and have many many hours of hands on experience with coils, HV pulse caps, spark excited tank circuits etc. to let misunderstandings go unchallenged. If I come on a little strong it is only because I run very high power equipment and designed and hand built nearly all of it. … If all else fails… Put another megavolt through it. _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2589 Date: 01-03-94 17:31 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Dave, RQ>I saw a post of yours up on the net today and thought I would >drop you a line. How was your vacation? Hi Richard - just got back a few days ago. Vacation was fantastic! I was on a small ( 150 foot ) cruise ship with 50 passengers, 30 crew and 8 scientists nosing around the islands in the Sea of Cortez (between Baha and Mexico ) for 12 days. Seattle's cold and rainy and I wanna go back!!!!! <grin> RQ>I am interested is following up on your coiling activities, and >wanted to tell you that another conference regular has received a >copy of my tape and is going to be jumping back into coils after >problems with his first unit (failed to produce the promised >results). I sent him all of my notes, the plans for the spark Great! It is really reassuring to know that it *can* be done. Especially since the time I tried in high school, I built the basic "classic" coil and was not concerned with ground or anything like that. Got a few inches of wispy discharge that was barely visible in daylight and the coil got promptly broken down and the 15KV neon sign xformer got turned into a jacobs ladder for a local coffee house I was working in at the time. I left you another note mentioning that I will be starting up some serious coil building in the next couple weeks. I still need to make the capacitors and to wind the secondary and build the support for the primary. I will be calling local plastics places to find the best price on the polyethylene and some plexi scraps. I have some 3/4" bronze rod in my boat junk drawer and I'll turn the transformer protection gap out of that. I was wondering about some of the magnetically quenched gaps and was thinking of experimenting with embedding some cobalt-samarium magnets just under the gap faces. Maybe later… Anyway, needless to say, I will be keeping the tape rolling during the smoke test. My neighbors already think I am weird, this will cinch it. RQ>On another note I have seen a post from Jim Arconati wanting >information on strong EM field generators. I tried to drop the >hint that the Tesla Tank circuit is the only way to go if you >want maximum peak powers. No other circuit I have seen or worked >with can produce rapid, megawatt range, pulses. I did see someone asking about creating EMP, forgot the name but I replied mentioning using a capacitor and inductor triggered by a spark gap. I didn't know if they were just into individual pulses or a continuous oscillation. I'll keep an eye out. RQ>I hope you can find the time to get your cap, coil, and tank >circuit together in the next couple of months. I really am >looking forward to getting some video and/or photos of your work >in the near future. I am looking at about two months max to have everything working. My garage ( shop area ) is at the bottom of a driveway and I was thinking of just sinking a couple 10' sections of copper water pipe for the ground. I have a rotohammer and can punch through the cement drive. I was thinking of putting a valve on one end and running water through it while I was driving it into the ground. Should make it a bit easier. Also, I forgot if I had mentioned it but I picked up about 40' of really heavy 1" copper braid at Boeing Surplus as well as a big spool of #22 stranded teflon insulated wire. The wire is kind of fat - 25 turns / inch but it should be wonderful for a larger coil and also a magnifier. The total cost for both plus some office litter was under $60 - definitely a good deal! RQ>Good luck, and remember to "Tune for Maximum Smoke!" Thanks! and I will keep you posted! TTYL - Dave -!- b QMPro 1.51 b We have enough scientists; we need more hunchbacks, Igor. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2590 Date: 01-03-94 17:37 From: Dave Halliday To: Jim Arconati Subj: big magnetic pulse ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> JA> I'd like some ideas on generating a LARGE magnetic pulse or > JA> field. RQ>The Tesla Tank circuit is the pulse field generator. It uses a >spark gap switch to pulse discharge a HV cap through a large >coil. The EMFs produced are incredible as peak powers in this >circuit can easily reach many megawatts. My largest Tesla system RQ>I have a two hour video tape that shows the basic setup and >operation of several of these systems. The video has shots >showing gas discharge bulbs lighting at several feet away from >systems that were tuned to produce sparks, not pulse fields. >Modification to a system such as you desire would be very >minimal. Hi Jim - butting in here. I have been in correspondence with Richard for some time and I sent away for his tape. It is fantastic! Also, from your initial post, I thought that you wanted just a single pulse and not a continuous field. That is why I suggested what is essentially just a single shot tesla primary. If you can use a continuous field, then a straight Tesla Coil setup is definitely the way to go! Check with your local BBS to see back postings of the Tesla thread. Good luck! Dave -!- b QMPro 1.51 b The Electric Chair and the Clapper Switch. A great combo ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 04 Jan 94 16:55:00 From: Richard Quick To: Jim Arconati Subj: BIG magnetic pulse ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Okay Jim, here we go: You set up your huge bank of HV pulse discharging capacitors and charge them from a heavily protected HVDC power supply. The caps are discharged through a coil of any desired dimension. The pulse is switched and controlled by placing two quenched spark gaps in series with the inductance. By adjusting the gaps you will be able to achieve a non-oscillating pulse through the coil. Since the pulse is not oscillatory, your capacitance may be as large as you desire without having to worry about frequency changes (or power limits) as the circuit is scaled up or down according to needs. This means that the pulse can become extremely powerful as the capacitor bank value can be increased virtually without limit. The key to successful operation of this circuit are the quenched spark gaps used in series with the inductance. They must quench extremely fast at very high power and they must be very high Q to produce a nice sharp pulse. This type experiment is something I have never exactally performed intentionally, but my Tesla work parallels these circuit designs very very closely. As I have mentioned, a slight modification to any of my present tank circuits would result with a spark excited EMP generator of exceptional power. If you are really serious in exploring this further I can offer specific help. I have designs on file (GIF) for a very high Q, air blast (quenching) spark gap designed for these high powers. I also have several files concerning the HV pulse discharging capacitors. I have archived the 10KVA Tesla Coil thread since 10/5/93 and the file contains over 100 pages of posts with specific and related information on these type systems and sub- systems. If you are interested in obtaining these text and GIF files send me a 3.5, 1.44 blank formatted disk and a SASE and I will send those to you post haste; there is no charge for the information. The video tape is also recommended for those interested in very high power spark gap oscillators, it details things like: HV power supplies, control circuitry, HV RF choking and 60 cycle filters for the power supply and control circuits, spark gaps, coils, Jacob's Ladder (20 kv @ 8 kVA), etc.. The tape shows everything in operation, complete with the monster discharges from my big coil. I charge $10.00 for a 2 hr SP recorded one-off master. You must send me a blank (high quality) VHS tape, and a self addressed first class postage pre-paid mailer. I mail the tapes out within 48 hours from receipt of your package and I will guarantee you will be glued to the TV for the entire tape. Every time I offer this tape I must make the following disclaimer: I cannot be responsible for the safety of anyone who replicates or attempts to replicate any of the systems or experiments featured on my video. The tape features nothing but high voltage, high energy systems any of which are quite capable of killing a person instantly or damaging valuable equipment. My address is: Richard T. Quick II 10028 Manchester Rd. Suite 253 Glendale, MO 63122 USA I am available in this conference to answer any questions or comments you may have regarding the contents of the video should you choose to pop for a copy but the thread archives offer detailed text explainations for much of the contents of the video as I have already sent out several tapes to some of the regulars here. I have had no complaints regarding the quality of the presentation. Good luck, and as always… … If all else fails… Put another megavolt through it. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2736 Date: 01-05-94 09:58 From: Robert Taylor To: Richard Quick Subj: Re: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ Quoting Richard Quick to Robert Taylor ⇐- RQ> When serious research is done with any Tesla patented system or RQ> device it becomes all too clear that Telsa's world was based on RQ> well thought out and workable systems. Bingo! Couldn't have put it better myself. The guy was definately a genius & at least 100 years before his time. The shame is that most people don't remember him for much past polyphase AC, high freq transmission, & synchronous motors when there was a ton of useful stuff beyond that. Later… … …and in a strange turn of events, the cat was electrocuted. -!- Blue Wave/Max v2.12 [NR] ! Origin: BLUFF CITY BBS - Under OS/2 - Memphis, TN (901) 763-3784 (1:123/70) ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2675 Date: 01-05-94 10:57 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>Hey Dave! RQ>Glad to have you back, and glad you had a good vacation. I wonder >how you fanangled such a trip??? I finagled it the old fashioned way, called up the tour agent and charged it. <grin> I like to get as far away from the telephone at least once a year wether I need it or not. Keeps me sane ( relatively ) RQ>Good Luck at Boeing with getting the heavy variacs, sounds like RQ>You made some good choices on picking up the heavy 1" strap and >teflon wire. Building up supplies took me months before I got to >the point that I did not have to run out every 15 min. looking >for such and such as I expanded my coiling. I will be going to Boeing today ( office person was also out of town and her plane did not get in on time yesterday ) They have a really funny pricing on stuff, some things are absurdly low, other things are way over what they should be. The good thing is that if you catch someone in a good mood, they will be open to any offer just to move the item. I am keeping my fingers crossed on this one! Also, re: running out every 15 minutes… I know that feeling. I get to the point where I think that I have a good parts collection and then my next project needs something that I never even heard of… My basement is getting to the point where space *is* the final frontier… <grin> RQ>Your ground idea sounds great. Space the pipes about 5' min >distance apart and wire them together with the 1" strap using >soldered connections. Water pumped into the pipes is an excellent OK - the garage is in the basement and the driveway slopes down to it. It is only 12 feet wide, I was thinking of spacing them closer than that. Another idea is that since the garage is on one edge of the house, I could just run pipes along that edge and bring the strap in through a window. My power panel is also in the garage so I could use it for the house ground as well… >idea. If you are going through the effort of pressure water >injection into the ground site go a step further and drill a few >small holes into the pipe sidewalls and get as much surface area >wet as possible. Salt added to the water (or poured into the pipe Very good idea! Seattle is kinda wet most of the time but we do have a couple weeks in the summer when it gets dry. You can see the locals running around with spray bottles misting down the mildew and moss on the houses… <grin> >before it is pressurized) will increase the local conductivity The salt is also a really good idea! I could pack the pipes with sea salt or make an "injector" out of some large diameter PVC with a hose fitting on each end. I have a nice garden ( yet another #$%^&* hobby ) but that edge of the house is nowhere near it so there would not be any damage to plants. >and improve your ground. A larger pipe or tin can may be set >around the grounding pipe where it enters the earth and may be >filled with water to trickle down around the ground. Use your >imagination. Just thinking that there is a gutter runoff is on that side too - divert the water from that… RQ>Constructing a good ground is very hard work, but essential to >performance coiling. You are wise to choose this often neglected It does make sense - I was into ham radio a while ago and know a little bit about antennas and can appreciate what a good ground plane can do. I shudder to see some boats with fiberglass superstructures and see that people have mounted ground-plane whip antennas on them and they then gripe about how poor their radio is, can't get a good signal out of it… Also cars where the antenna is mounted on one corner of the roof - nice omnidirectional radiation pattern there… <grin> >area as your starting point, and your neighbors will be thankful >(it really does limit the RFI). Nothing ruins a guys day like the >neighbors showing up at the door with torches in their hands > a la Frankenstein… Actually, considering the neighborhood, that's a fun image! The area I am in was built in the 50's and has a lot of the original owners in there. I can see my next door neighbors in particular. They are really good people but the guy retired about 20 years ago ( Boeing engineer ) and does not have any real hobbies except snooping into what I am doing. I'll have the garage door open and be working on something and he will totter over and talk for a long time, grousing about the state of the world in general. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2679 Date: 01-05-94 16:40 From: Dave Halliday To: Richard Quick Subj: Tesla goodies ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Hi Richard - just got back from Boeing Surplus. I took a good look at the high voltage supply. Made by HiPot, rated for 60KV at about 100-200 milliamps. It would have been really nice to get but it was *huge*. The main transformer tank stands about four feet tall and then there is the control unit, an eight foot tall enclosed rack. But the good news is that I also saw a triple-gang, motorized 50 Amp Powerstat unit there, priced at $300. I offered $100 and we settled on $150. Since it is motor controlled, I will just put it right near my main breaker panel and then run a conduit out to where I will be running the coil. This will be really nice too in that my control box can be smaller. For safeties sake, I will probably have a relay to disconnect the Powerstat and have a pushbutton switch on it that needs to be pushed every time I want to fire the coil. That way, if I have a small hand-held control box, I will not have the chance of it firing up accidentally. Also, going through the back mail from when I was away, I got the January issue of the TCBA News and my membership certificate. Looks really well written, I will send away for some back issues. I will keep you posted - Dave -!- b QMPro 1.51 b Wench: What you use to turn the head of a dolt… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2680 Date: 01-05-94 17:25 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ>We are talking about placement and construction of a heavy RF >ground using two 10' lengths of copper water pipe… RQ> DH> OK - the garage is in the basement and the driveway slopes > DH> down to it. It is only 12 feet wide, I was thinking of > DH> spacing them closer than that <5' apart>. RQ>Your ground will have lower resistance to heavy RF current >(higher Q) if you space the pipes out about half of their length. >If the placement does not allow separation you are better off >just using one pipe. The reason for this is closely placed >grounding points will effectively act as a single point. The more >you space, the bigger the electrical ground produced. OK - got that. Thanks for the info. I will probably put the ground on the outside wall of the house alongside where the garage is. There is a property line there so I have a good long run to play with. I will need to get some more of that braiding but Boeing seems to always have a lot of it on hand. They charge $1.50 / pound. RQ> DH> My power panel is also in the garage so I could use > DH> it for the house ground as well… RQ>Don't make permanent connections from the coil (RF) ground to the >house ground. This will allow RF bleedover and RFI problems. You >may make connections here when coils are not being fired, but >keep the control cabinet and the house ground at lower potential >than the RF ground. In other words when the RF ground is in use >grounding a coil it is "powered up" and full of RF current and >hash (RFI). If you connect your power cabinet to it then RF will >bleed into the house through the power cabinet 60 cycle ground >connection. Isolate the RF ground from other equipment. Got it! That makes a lot of sense - even though there is a good ground, there is still a *lot* of current flowing into it and there could be some problems with bleedover. Nothing like being able to draw a three foot long arc from my refrigerator. It would be a great hit at parties… I will just keep the electrical panel just as it is and make the Tesla ground completely separate. I am also thinking of this summer, renting a generator and setting up a coil at the pier near Lake Washington and using a couple foot square aluminum sheet in the lake for the ground. The park I live by is used a lot for picnickers and such so it might get a bit of attention… A Seattle man was arrested today for… <grin> TTYL for now - Dave -!- b QMPro 1.51 b Proofread carefully to see if you any words out. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2678 Date: 01-05-94 17:29 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ We are talking about placement and construction of a heavy RF ground using two 10' lengths of copper water pipe… DH> OK - the garage is in the basement and the driveway slopes DH> down to it. It is only 12 feet wide, I was thinking of DH> spacing them closer than that <5' apart>. Your ground will have lower resistance to heavy RF current (higher Q) if you space the pipes out about half of their length. If the placement does not allow separation you are better off just using one pipe. The reason for this is closely placed grounding points will effectively act as a single point. The more you space, the bigger the electrical ground produced. DH> My power panel is also in the garage so I could use DH> it for the house ground as well… Don't make permanent connections from the coil (RF) ground to the house ground. This will allow RF bleedover and RFI problems. You may make connections here when coils are not being fired, but keep the control cabinet and the house ground at lower potential than the RF ground. In other words when the RF ground is in use grounding a coil it is "powered up" and full of RF current and hash (RFI). If you connect your power cabinet to it then RF will bleed into the house through the power cabinet 60 cycle ground connection. Isolate the RF ground from other equipment. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 06 Jan 94 12:34:30 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> But the good news is that I also saw a triple-gang, DH> motorized 50 Amp Powerstat unit there, priced at $300. I DH> offered $100 and we settled on $150. Since it is motor DH> controlled, I will just put it right near my main breaker DH> panel and then run a conduit out to where I will be DH> running the coil. This will be really nice too in that my DH> control box can be smaller. For safeties sake, I will DH> probably have a relay to disconnect the Powerstat and have a DH> pushbutton switch on it that needs to be pushed every time I DH> want to fire the coil. That way, if I have a small hand- DH> held control box, I will not have the chance of it firing up DH> accidentally. Your looking good. You should have no problems with current overload with these units even running a pole pig. Powerstats are commercial cont. duty rated and will handle a run at twice the plate rating for 5 min. or more before they warm up. If required you can use a cooling fan for real high current experiments. Good job on hunting down the right componet for the job. Power relay safety interlocks are a very very good idea. I run two in my power cabinet, one before the variac and one after the variac. The first power relay interlock is tripped by key switch to prevent unauthorized powerup of the cabinet, the second interlock is switched with a toggle (cont. operation) and push button (manual pulse operation). Be sure to ground the variacs to the breaker box with #6 copper min. and to the water pipe with some more of that 1" strap. I use a separate 240 v breaker box with plug-in replaceable breakers (60 amps currently) on the feed to my cabinet/variacs. DH> Also, going through the back mail from when I was away, I DH> got the January issue of the TCBA News and my membership DH> certificate. Looks really well written, I will send away DH> for some back issues. Collecting back issues of the news is a good idea. I have issues dating back to 1988 and pop for another years worth of back issues every time I renew. I have seen some dynamite articles (I have been published here as well) and some really excellent coil projects… One issue had a guy's coil powered by a 455 Olds engine running a three phase 480 volt generator. The coil design was unfortunately "classic" in origin though modern construction and materials were used, but the article published the complete schematic for the generator/control circuits. You will find some really interesting stuff here. Back on that ground for just a second. Make sure the pipes are driven in away from basement foundation walls by at least 5'. If you are putting the pipe in near a garage (built on a slab with no basement foundation) it will be no problem to place ground pipe right near the structure. The reason for this of course is that a basement foundation wall only contacts earth on one side, and grounding rod or pipe driven here will only conduct 180 degrees of a circle instead of all 360. Keep up the good work! … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2712 Date: 01-06-94 15:37 From: Dave Halliday To: Richard Quick Subj: tesla stuff… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Hi Richard - I was wondering if you had Walt Noon's address. You had mentioned that he had a design program and I just saw that the Tesla Bookstore in Chula Vista, CA carries it. I would rather get it directly from him because he probably wholesales it to the bookstore and I would rather have him get the money. I got the PowerStat temporarily hooked up and it runs fine! The motor takes about 30 seconds to go from one end to the other. I didn't really throw a load on it, just a 500 watt quartz-halide floodlamp but it seems to be in like-new condition. Thanks again for all the info - I will be keeping you posted - Dave -!- b QMPro 1.51 b Bureaucrats are the meat loaf of humanity. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2713 Date: 01-06-94 15:47 From: Dave Halliday To: Richard Quick Subj: tesla ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Hi Richard - forgot to mention in the last message but I just realized that two days from now we will have the 50th anniversary of Tesla's death. ( 7 Jan 1943 ) Maybe coilers around the world should power up for a minute in commemoration… Dave -!- b QMPro 1.51 b In New Guinea: cargo cults. In the U.S.: vaporware. ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2714 Date: 01-06-94 17:47 From: Dave Halliday To: Richard Quick Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ RQ> DH> But the good news is that I also saw a triple-gang, > DH> motorized 50 Amp Powerstat unit there, priced at $300. I > DH> offered $100 and we settled on $150. Since it is motor RQ>Your looking good. You should have no problems with current >overload with these units even running a pole pig. Powerstats are >commercial cont. duty rated and will handle a run at twice the >plate rating for 5 min. or more before they warm up. If required >you can use a cooling fan for real high current experiments. Good >job on hunting down the right componet for the job. I kinda figured they would do the trick when I saw them. I'll have to include a shot of them when I send you the video. They are *huge* The whole assembly must weigh at least 250 pounds! RQ>Power relay safety interlocks are a very very good idea. I run >two in my power cabinet, one before the variac and one after the >variac. The first power relay interlock is tripped by key switch >to prevent unauthorized powerup of the cabinet, the second >interlock is switched with a toggle (cont. operation) and push I think so too. I have had some near misses because I *knew* that everything was turned off and safe… I am very cautious. When changing the blade on my table saw, I will un-plug it from the wall and drape the cord over the saw table so I can look at it while changing the blade… There is no one else at the house ( except for two shepherds ) but something could fall on the switch or I could trip and put a hand out on the wrong thing… The key switch is one idea I hadn't thought of and the idea has just been swiped! <grin> I can imagine my leaving the garage door open some day and having a neighborhood kid walk in out of curiosity… The idea with the relay was that whenever the coil was powered down, the relay would drop out and I would have to walk over to the PowerStat and hit a button to reset it. That way, if I have a hand-held remote, there would be no way I could fire it from the remote without first engaging the relay. The same relay would also be connected to the kill button on the remote. I have also been thinking that since I use the little five-amp Variac on my test bench at the store but I do most of my home-brew electronics at the house, I could also run a line from the PowerStat to my workbench for testing electronics stuff. Kill two birds with one stone - blow things up with the coil and then fix them on the bench… <grin> >button (manual pulse operation). Be sure to ground the variacs to >the breaker box with #6 copper min. and to the water pipe with >some more of that 1" strap. I use a separate 240 v breaker box >with plug-in replaceable breakers (60 amps currently) on the feed >to my cabinet/variacs. Yeah - I was thinking of putting a 60 amp breaker in the main box, then coming off of that to a smaller box ( maybe with a couple of 60 amp fast-blow fuses ) and using that box to connect to the PowerStat. I would then have a commercial ( Industrial grade ) electronics box conduited to it holding the relays and the control electronics. I was also thinking of picking up two current shunts so I could instrument the puppy a bit. RQ> DH> Also, going through the back mail from when I was away, I > DH> got the January issue of the TCBA News and my membership RQ>Collecting back issues of the news is a good idea. I have issues >dating back to 1988 and pop for another years worth of back >issues every time I renew. I have seen some dynamite articles (I >have been published here as well) and some really excellent coil I noticed that the quality of writing was really good. Much better than Boarderlands or any of the "fringe" types. Actual legible circuit diagrams… Stuff like that… <grin> >projects… One issue had a guy's coil powered by a 455 Olds >engine running a three phase 480 volt generator. The coil design >was unfortunately "classic" in origin though modern construction >and materials were used, but the article published the complete >schematic for the generator/control circuits. You will find some >really interesting stuff here. That would be something to see! RQ>Back on that ground for just a second. Make sure the pipes are >driven in away from basement foundation walls by at least 5'. >If you are putting the pipe in near a garage (built on a slab >with no basement foundation) it will be no problem to place >ground pipe right near the structure. The reason for this of >course is that a basement foundation wall only contacts earth on >one side, and grounding rod or pipe driven here will only conduct >180 degrees of a circle instead of all 360. I was thinking of that. My initial plan was to run them down the side of the house but taking a walk out there made me realize that I would be loosing half of the ground. The property line is about 8 feet away so I will run it there. That particular line is the one I share with my grumpy neighbor so it should be a fun time putting them in. Your'e doing what??? For *what*??? What's a "Tesla Coil" anyway??? RQ>Keep up the good work! Thanks for the info/advice/help! TTYL - Dave -!- b QMPro 1.51 b «< Tagline deleted by Natl Endowment for the Arts »> ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 1 Date: 06 Jan 94 22:14:20 From: Richard Quick To: Dave Halliday Subj: tesla stuff… ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ DH> Hi Richard - I was wondering if you had Walt Noon's address. DH> You had mentioned that he had a design program and I just DH> saw that the Tesla Bookstore in Chula Vista, CA carries it. Walt and I are good friends. I have helped him debug, add features, and made other suggestions that he incorporated into the software. It works. Please do write to him and let him know I am recommending his software in the conference. I owe him a letter still, so send my regards and tell him the halloween photos were appreciated. Walt Noon III 3283 Belvedere Riverside, CA. 92507 DH> I got the PowerStat temporarily hooked up and it runs fine! DH> it seems to be in like-new condition. Cool dude, you be entering the world of high voltage soon. -!- … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 2 Date: 06 Jan 94 22:20:57 From: Richard Quick To: Robert Taylor Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ -⇒ Quoting Richard Quick to Robert Taylor ⇐- RQ> When serious research is done with any Tesla patented system RQ> or device it becomes all too clear that Telsa's world was RQ> based on well thought out and workable systems. RT> Bingo! Couldn't have put it better myself. The guy was RT> definately a genius & at least 100 years before his time. RT> The shame is that most people don't remember him for much RT> past polyphase AC, high freq transmission, & synchronous RT> motors when there was a ton of useful stuff beyond that. RT> Later… The shame is that most people don't remember Tesla at all :-( -!- … And if all else fails… Put another megavolt through it ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Msg#: 3 Date: 06 Jan 94 22:32:13 From: Richard Quick To: Dave Halliday Subj: 10KVA Tesla Coil ŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽŽ Just read your other posts. The ground seems to be well planned and thought out. Go with it, it will work great and will be expandable when you go to put a bigger coil on it. Your safety and protection system ideas sound level headed, and should work fine. Just don't forget to wire them in for those first few test runs. The aniversity of Tesla's death should be celebrated with everyone switching off the electrical mains into their houses, then maybe people would begin to appreciate what he gave to mankind…. That HE was the one that brought power to the world!!! -!- … If all else fails… Put another megavolt through it. ====================================================================== ===== Date: 07-01-94 (11:18) Number: 2504 From: DAVE HALLIDAY Refer#: NONE To: RICHARD QUICK Recvd: NO Subj: 10KVA TESLA COIL Conf: (218) Electronic ———————————————————————- —– RQ>Just read your other posts. The ground seems to be well planned >and thought out. Go with it, it will work great and will be >expandable when you go to put a bigger coil on it. I was a ham for a while and also worked on some FM stations when I was in college and I can appreciate the value of a good ground. I am also into overbuilding anything that I can get my hands on. Takes more time at the beginning but it never breaks later… RQ>Your safety and protection system ideas sound level headed, and >should work fine. Just don't forget to wire them in for those >first few test runs. This is a very astute comment. Patience has never been one of my virtues and I have to force myself to complete some of the things I work on instead of just running with them when they get to a certain level… Rest assured though that I fully appreciate the dangers of the high voltages involved here… I have been "bit" a few times with tube equipment and have no desire for that to happen again! RQ>The aniversity of Tesla's death should be celebrated with >everyone switching off the electrical mains into their houses, >then maybe people would begin to appreciate what he gave to >mankind…. RQ> That HE was the one that brought power to the world!!! This is so true! That would be something to do - turn off the main breaker for ten minutes. The more and more I read about his work, the more I realize just how much everyone *else* derived from his ideas! Anyway, TTYL - Dave b QMPro 1.51 b Hey, don't pick up that dogW‚.™ … D NO TERRIER — WM v3.10/93-0100 * Origin: St. Louis Users Group BBS (314) 878-7614 (1:100/4.0) (1:100/4) ====================================================================== ===== BBS: WELCOM BBS Date: 21-02-94 (10:57) Number: 3295 From: RICHARD QUICK Refer#: NONE To: BRIAN CARLING Recvd: NO Subj: 10KVA Tesla Coil Conf: (111) ELECTRONIC ———————————————————————- —– L1 T1 뀎Ž‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹ŽŽŽŽ‚ £‹‹‹‹‹‹‹‹‹‹‹ŽŽŽŽŽ¨ 3 L2 3 3 3 G1 O 3 O 3 3 C1 3 ~AŽŽŽŽŽŽ' ~AŽŽŽŽŽŽŽ' 3 3 3 3 3 3 …‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹‹— X1 ¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡ŽŽŽŽŽë £ŽŽŽŽ‹‹‹‹‹‹‹‹ŽŽŽŽ¨ 3 3 3 3 60 Hz Line In L1 = Tesla secondary coil. T1 = Discharge Terminal L2 = Tank Circuit Primary Coil G1 = Tank Circuit Spark Gap C1 = High Voltage, Pulse Discharging Capacitor X1 = High Voltage Step Up Transformer Power to drive the circuit is normally 60 Cycle 120/240 fed to a step up transformer (Neon sign, potential, power distribution, or plate type). The step up xfrmr charges capacitor C1 in the Tank Circuit. When C1 is fully charged, the voltage breaks down the air at the main system sparkgap <G1>, which sets the Tank Circuit into a high frequency oscillation. The specific frequency of oscillation is determined by the value of C1, and the inductance (# of turns) in the primary coil L2. L1 is grounded at the base, as is the case and core of X1. L1 is fitted with a conductive discharge terminal on the ungrounded (air) end of the coil. This is among the simplest circuits that Tesla patented, and is a good start for a beginner. A typical Tesla secondary in this circuit (L1) may be constructed by close winding about 1500 feet of #22 double Formvar coated magnet wire on a 6" diameter section of dried PVC thin wall drain pipe that has been well sealed with polyurethane or two part epoxy paint. The coil should be around 24" high (no more than 30") and tightly, evenly wound with a single layer of wire. Leave about an inch of coil form above and below the windings. The coil is capped top and bottom with 1/4" plexiglas plates glued on with expoy. No holes are drilled into the sides of the PVC coil form. Once the coil is wound, it is again sealed with polyurethane or two part epoxy paint to prevent breakdown. L2, the Primary Coil, is wound from 60-75 feet of 3/8" OD soft copper water pipe or refrigerator tubing. Wind the coil in a flat, pancake, spiral on some plastic insulating supports. The inside turn should be about 9-10 inches in diameter, with turns spaced about 1/4" apart. The finished coil should be about as wide as coil L1 is long, or a little wider. C1 has typical values around .009 - .02 uf (microfarads) with a voltage rating between 10 - 20 killovolts AC. For best performance the capacitor should be pulse rated for rapid discharge. T1 is the secondary coil discharger. A beginner might throw a 4-5 inch diameter spherical aluminum flag pole top on the coil for a discharger. A Toriod (donut shaped) discharger will give higher breakdown voltages, and longer sparks. G1 is the main system spark gap. Two solid brass utility door knobs from the hardware section at Walmart may be mounted on an insulating support. With the smooth knobs facing one another, and at least one knob made movable for adjustment, they will serve well for low power coiling for a beginner. X1 for most beginners is the common Neon Sign xfrmr. The higher voltage units are best, but you must not exceed the voltage rating of your capacitor C1. To increase the current to charge the capacitor you may run several neon sign xfrmrs in parallel. … And if all else fails… Put another megavolt through it _ Blue Wave/QWK v2.12 — WM v3.10/93-0100 * Origin: St. Louis Users Group BBS (314) 878-7614 (1:100/4.0) (1:100/4) ====================================================================== ===== BBS: WELCOM BBS Date: 27-04-94 (20:00) Number: 5940 From: RICHARD QUICK Refer#: NONE To: DAVE HALLIDAY Recvd: NO Subj: 10KVA Tesla Coil Conf: (111) ELECTRONIC ———————————————————————- —– Dave, I thought I would take a minute to cover some aspects of RF choking on the feed lines to the Tesla Tank circuit. I will refer you to vol. 13, #2, page 6 of the Tesla Coil Builders Association publication NEWS for a start. Since others will be reading this, and will not have access to this publication, I will reproduce the circuit diagram below. PC1 X1 RFC 1A RFC 2A ŽŽŽŽŽŽŽŽƒŽŽŽŽŽŽ¨§£ŽŽŽŽŽŽ‹‹‹‹‹ŽŽŽƒŽŽŽŽ‹‹‹‹‹ŽŽŽ> TO TESLA TANK Ž Ž )§( 3 ŽƒŽ )§( 3 3 )§( O .€ŽŽŽ' )§( .€ŽŽŽŽo SAFETY GAP 3 )§( O Ž Ž )§( 3 ŽƒŽ )§( 3 ŽŽŽŽŽŽŽŽ ŽŽŽŽŽŽ—§…ŽŽŽŽŽŽUUUUUŽŽŽ ŽŽŽŽŽUUUUUŽŽŽ> TO TESLA TANK PC2 RFC 1B RFC 2B "Radio Frequency Chokes RFC 1A and 1B are wound with about 70 turns on a 1" cylinder (PVC, plastic, etc.). RFC 2A and 2B are wound with around 20 turns on a similar form. The size of the wire is not critical as long as the wire is capable of carrying the rated current." "Protective Capacitors PC1 and PC2 are not critical and can be rated in the vicinity of .5 to 2 microfarads. Use a voltage rating as high as possible. The usual 400-600 volt capacitors will not withstand kickbacks for very long. I prefer capacitors with ratings of from 2500 to 5000 (or higher) volts" The above is quoted from the article, X1 is of course the high voltage step up transformer that supplies the Tesla Tank. I will note that this circuit is the bare minimum protection required, and that this is only adequate for small (6") coils running under 1.5 KVA. Even the author, Harry Goldman, admits that this RF protection circuit does not eliminate, but only reduces the RF and kickback problem. Note his statement that the low voltage line PC (Protective Capacitors) capacitors (PC1 & PC2) need a rating of 2500 volts or higher. These capacitors are across the 120 or 240 volt 60 cycle line!!!! Imagine what voltage spikes are appearing in the house or shop supply line if 400-600 protective capacitors are routinely failing. Obviously the problem needs some more attention. Please note the modifications to the above circuit in my recommended circuit below. £——¨ | | X1 RFC 1A ŽŽ|ŽŽŽŽŽŽ|ŽŽŽŽŽ¨§£ŽŽŽŽŽŽƒŽŽŽŽŽŽŽŽƒŽŽŽŽ‹‹‹‹‹ŽŽŽ> TO TESLA TANK | | )§( 3 3 | | )§( 3 3 | | )§( BC1 Ž Ž O | LF1 ~AŽ. )§( ŽƒŽ oŽŽ. SAFETY GAP | | )§( 3 O | | )§( 3 3 | | )§( 3 3 ŽŽ|ŽŽŽŽŽŽ|ŽŽŽŽŽ—§…ŽŽŽŽŽŽ ŽŽŽŽŽŽŽŽ ŽŽŽŽŽUUUUUŽŽŽ> TO TESLA TANK | | 3 RFC 1B …——— ¡‹¡ grnd LF1 is a commercial heavy duty line filter wired in reverse. Where current throughputs are high I use several in parallel. Quality commercial line filters employ iron powder chokes, as well as the "PC" capacitors of the circuit at the top of this post. The Line Filters I use also have RF choke coils in the ground path; the ground wire can be run reversed (it is neutral) and can be used to trap stray RF, preventing ground path contamination to the 60 cycle breaker box. I should note that I use a minimum of two independent grounds. The core of X1, and everything to the right of X1 in this diagram, is grounded separately to a heavy, dedicated, RF ground. This heavy RF ground is also used to ground the base of the Tesla secondary. Note that the core of X1 is grounded in this diagram, where the top diagram shows the core floating ungrounded. I believe this was an oversight of Mr. Goldman's. BC1 is a Bypass Capacitor. I use high voltage barium titanate doorknobs, with stacks of four or more in series. A typical rating for a single cap would be .003 microfarad @ 30 KVDC, and using four of these caps in series I get .0007 microfarads at 120 KVDC. Since the AC rating is about half the DC rating on these type capacitors, figure a series stack of four will withstand a kickback of 50-60 KVAC in this use. Where center tap ground type xfrmrs are used for X1 (such as neon sign cores) BC1 must be divided into two units, and the center of the stack must be grounded with the xfrmr core (see the arrange- ment of PC1 and PC2 in the top most diagram). Use no more than .0008 or so microfarads per side, as too large a bypass capaci- tance will create an oscillating current in the high voltage windings on your step up xfrmr that will cause the xfrmr to fail. RFC 1A and RFC 1B are about 15-20 turns (minimum) of insulated wire on a large iron powder core. I use 2" diameter iron powder toroids to wind these chokes. I have found that the RF and Kickback protection of the circuit using bypass capacitors and iron powder (as opposed to air core) RF chokes is much better than the simpler circuit recommended by Mr. Goldman. If you are running a small tabletop Tesla coil, then Mr. Goldman's circuit is probably all you need. But if you are running, or intend to run, more than 1.5 KVA out of your power supply; look carefully at the circuit I have outlined. Remember… Over 1.5 KVA and the kickbacks are sounding like high powered rifle shots at the safety gap. They will "light up your life" if not properly contained and grounded. … If all else fails… Throw another Megavolt across it! — WM v3.10/93-0100 * Origin: St. Louis Users Group BBS (314) 878-7614 (1:100/4.0) (1:100/4) ====================================================================== ===== Date: 03-05-94 (21:05) Number: 6265 From: RICHARD QUICK Refer#: NONE To: BLAIR GROVES Recvd: NO Subj: 10KVA Tesla Coil Conf: (111) ELECTRONIC ———————————————————————- —– BG> Hi Richard, I've been reading about a monster Tesla coil BG> you've made, but got into this echo a bit too late to hear BG> the important stuff… can you fill me in on it? (like, how BG> big is this beast, and what can you do with such a thing?).. The coil is not very big. The actual coil featured on the video is 10-3/4 inches in diameter. The winding is a single layer of #21 magnet wire, 1024 close spaced turns, making a winding length that is only 32", on a form that totals 35" in height. But the sparks from this coil have exceeded 14 feet in length… I have imported some stuff from my archives (which are extensive) to answer in more detail… >What can a person do with such a device once constructed? Does >it have any practical purpose other than to amuse your friends? I first began to build small 1/4 wave (spark generating) Tesla coils for fun. I loved the light show, and so did my friends. As I gained experiance in building coils I realized that most of the "plans" were full of inaccuracies. I began to design my own systems to increase efficiency. As my interest and experience grew, I discovered more advanced coil systems that Tesla designed (the Tesla Magnifier) and began initial research into other areas: particle acceleration, lasers, wireless power transmission, and particle beams. I am planning on making a very serious study in these areas in the next few years. Dave Archer is a painter in California who uses a Tesla coil to electrically spread paint. He places his canvas on a grounded plate and directs the Tesla discharge over it. The resulting paintings are regularly featured as space backgrounds and hanging art on Star Trek TNG, Omni Magazine and several other publica- tions, as well as private collections. Tesla coils were also used in the time travel scenes in both Terminator movies, and are re- emerging in the special effects industry because they photograph well and the sparks are more realistic than computer generation or animation. Tesla coils were used in the first induction heaters, and were employed medically for the treatment of arthritis and other joint and muscle problems. The same coil could be adjusted to generate sufficient voltage to produce X-Rays, and as such a Tesla coil was a standard medical instrument in Dr's offices in the early 1900s. Nearly all of the first high quality X-Rays were produced with Tesla driven X-Ray tubes until the 1930's. The first self cauterizing "electric scalpels" were electrified with a Tesla coil. A Tesla coil is in your monitor (flyback transformer). Tesla coils were also an important part of the first radio transmitters. My feeling is that the Tesla coil has a major place in modern physics, but has not been fully evaluated. The 1/4 wave Tesla coil (sweet and simple, though there are other configurations) is an oscillator driven, air core resonate transformer. The oscillating tank circuit drives the secondary coil. The tank circuit consists of pulse discharging capacitors, air gap (spark gap, break) and the primary coil. I said the setups are very flexible, so I will focus on specs for the 10KVA coil. The primary coil is wound from a single 100' length of 1/2" soft copper water pipe placed on plexiglas stand off insulators. The inside turn starts at 14" in diameter, and the turns wind outward to form a flat pancake spiral, like the grooves on a phonograph record. The outside turn is 36" diam.. There are a total of 15 turns in this coil, spacing between turns is 1/4". I own two .1 mfd 45 kvac pulse discharging capacitors. These two custom commercial units were purchased to supplement my 14 homemade polyethylene/aluminum flashing/mineral oil units rated at .02 mfd 10 kvac pulse. With the 10 KVA coil I use the two commercial "caps" in series with the primary, so the actual operating capacitance is only .05 mfd. (rated 90 KVAC though…). I connect the capacitors to the primary coil and the spark gap. By using a movable "tap" lead which can clip to any location on the heavy primary coil, the primary coil inductance is varied, and the tank circuit frequency can be changed or "tuned". The spark gap acts as a high voltage switch. When the gap is open, the capacitors charge. When the gap fires, the caps are discharged in a pulse. Because of the voltage and currents involved, the gaps on larger coils employ a rotary break, almost exactly like a large car distributor at high speed. This pulse discharging produces a large current (over 1000a@20kv in my system) from a modest transformer output (.5 amp @ 20kv). The pulse "rings" (oscillates) from capacitor plate, through the coil, and back. The secondary coil has a natural electrical resonate frequency dependant mostly on wire length. It may be modified or tuned by addition or subtraction of top capacitance or "discharge terminal". The two coils are tuned to the same frequency, and then energy is xfered from the primary to the secondary. This is the resonate transformer theory. BG> Also, I'm interested in making a Jacob's Ladder. Do you have BG> any plans or ideas on that? All you need is a neon sign xfrmr and a couple of coat hangers. Neons have built in current limiting. Do not construct a Jacob's Ladder with an xfrmr that is not current limited. … If all else fails… Throw another Megavolt across it! _ Blue Wave/QWK v2.12 — WM v3.10/93-0100 * Origin: St. Louis Users Group BBS (314) 878-7614 (1:100/4.0) (1:100/4) ====================================================================== ===== BBS: WELCOM BBS Date: 07-08-94 (21:31) Number: 10768 From: RICHARD QUICK Refer#: NONE To: DON KIMBERLIN Recvd: NO Subj: Tesla Coils Conf: (111) ELECTRONIC ———————————————————————- —– RQ> DK> …Nice sketch: RQ> DK> …but where do you plug the microphone in? <smirkle> Human voice T1 \/ 3 ýŽŽŽƒŽŽŽý←-Diaphram 3 L2 ý § V ý←-Valve ~AŽŽŽŽŽŽŽŽ} ý § § ý 3 } ¡¡¡¡‹¡¬á§áááá 3 } Gas in^ § 3 } Gas out> § 3 } § A1 3 } L1 C1 Š¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡ »» } {ŽŽŽ'~AŽŽŽƒŽŽŽ < HF Gas stream> 3 } { o 3 } { G1 o 3 } {ŽŽŽŽŽŽŽŽ ŽŽŽ < HF ~AŽŽŽŽŽŽŽŽ} 3 earth ëëë RQ>The "gas under pressure" microphone was placed in the circuit RQ>between the air capacity terminal (T1) and the ground. The RQ>modulated air stream would in turn modulate the arc at A1. DK> …. DK> …Sonofagun! Old (young) Tesla had it all! Interesting DK> situation occurs when trying to modulate extremely low DK> frequencies, however. Unless the ratio between the DK> modulating (speech) and modulated (radio) sigs is more than DK> about 1:10, a lot of problems with distorted speech occur. Tesla mentions this effect several times in the COLORADO SPRINGS NOTES, both in reference to the circuit above, and in the carbon microphone circuits. He stated that the oscillations of the coil and the break rate on the gap had to be very rapid to reduce this effect and produce the clearest speech at the receiver; so it appears to me at any rate, that he was not only very aware of this problem, but that he had gone far towards solving it. DK> Still, if the technology had ever gotten to wide use, I'm DK> sure he would have worked that out… I think it was worked out. So many people fail to realize that Tesla designed and constructed not random inventions, but entire working systems. By "working systems" I mean things like the commercialized polyphase system in use today (and unchanged since Tesla first handed the patents to Westinghouse machinists). Tesla stated all the way up to the time of his death in 1943 that his wireless system was far superior to any system in use. The example above is drawn from his experimental work of 1899 and prior, as are the carbon microphone systems I mentioned (and provided references for). What I find particularly impressive: his system required no sensitve detector (receiver - amplifier), and no external power supply, for a person to hear human voice at the receiving end (the transmitter being very powerful and efficient at delivering energy). Tesla showed us fully developed triode vacuum tubes in 1891 in his public lectures (drawings, photos, and lecture transcriptions of the tubes exist). He was asked during his pending court case in 1916 why such tubes were not employed by him in receiver/ amplifier circuits. He answered that in his "system" they were not required: that no amplification was. He was clearly quite familiar with the design, construction, and operation of these tubes before Deforest; but did no further study with them because the knowledge and use of these tubes were not required for voice transmission. Tesla frustrates me time and time again for what he clearly documented but refused to employ/patent in some application; others grabbed credit for much of what was his original work. … If all else fails… Throw another Megavolt across it! — Blue Wave/RA v2.12 [NR] * Origin: Cindex Support BBS (314) 837-5422 Florissant, MO. (1:100/395.0) ====================================================================== ===== BBS: WELCOM BBS Date: 06-09-94 (16:52) Number: 12123 From: RICHARD QUICK Refer#: NONE To: JAMES MEYER Recvd: NO Subj: Tesla Capacitors Conf: (111) ELECTRONIC ———————————————————————- —– RQ> Flat plate caps have no inductance. Rolled caps contain two RQ> or more plates which are tightly rolled up. Rolled plates RQ> exhibit some properties of coils, they contain a certain RQ> degree of self-inductance. JM> Rolled caps don't always have to show a lot of inductance. JM> With a slight modification to your construction techniques, JM> you could make "extended foil" caps with almost no JM> inductance. The inductance of an extended foil cap doesn't JM> change as they get bigger either. Please tell me more. What slight modifications would be required, and how do those modifications reduce or eliminate self- inductance? As I may have mentioned; the .02 uf 10 KVAC pulse discharging rolled capacitor (instructions which I have posted here several times) are self-resonant around 1.2 MHz. When I build larger caps of this design; the self resonance drops below 1 MHz where it interferes destructively with the tank circuit operation of smaller coils; these smaller coils are where the beginners start. The second design limitation I have encountered is a lowering of the tank circuit Q factor when larger rolled caps are used in the oscillator. I attribute part of this to destructive self-reson- ance, but this can be controlled/reduced by operating the oscillator at lower frequencies, and maintaining a suitable spread between the self-resonate frequency of the cap, and the normal operating frequency of the oscillator. The destructive interference does not seem to account for the large drop in Q factor I read on my scope. One problem with tank circuits is that the circuit Q factor drops off as the physical length of non-primary coil conductors increase. I have run physically large oscillators below 100 kHz, using up to 14 of the homemade .02 uf rolled caps in the circuit at one time, and the Q factor gets pretty poor. The bus wiring alone subtracts plenty of Q (even with great care you get tons of radiant surface area and off-axis inductance); but when I add up all of the plate lengths of the rolled caps, and include these lengths as a factor in the tank circuit wiring, it becomes clear that the wiring length of the circuit exceeds the primary coil length by several times. It seems that this must be avoided. Where physically large layouts are common, that is at lower tank circuit frequencies (say below 175 kHz), I switch to flat stacked capacitors. When I switch, I see tank circuit Qs increase. This capacitor construction (flat plate) avoids the problem of self- inductance (&therefore self-resonance), but I see an increase in tank circuit Q that the self-inductance factor alone does not seem to account for…. It seemed to me the best course to limit the rolled cap design at .02 uf, and for larger capacitors, to switch over to a flat stacked capacitor design. I am not at all trying to detract from the viability of your suggestion, which I would like to hear in more detail, but I am simply trying to outline and clarify some of the problems and design limitations I have encountered in the course of my experimentation. … If all else fails… Throw another Megavolt across it! — Blue Wave/RA v2.12 [NR] * Origin: Cindex Support BBS (314) 837-5422 Florissant, MO. (1:100/395.0) ====================================================================== BBS: WELCOM BBS Date: 06-09-94 (18:24) Number: 12124 From: RICHARD QUICK Refer#: NONE To: TERRY SMITH Recvd: NO Subj: Tesla, Col.Sprng Conf: (111) ELECTRONIC ———————————————————————- My mail services have been poor to worse the last two weeks. No mail picked up for a nearly a week, then getting duplicates, not counting posts missed completely and late messages…. Anyway, Terry Smith and Don Kimberlin were commenting on some info I dug up on Tesla's Colorado Springs Magnifier…. TS> Interesting, yes, but nothing like what would be TS> characteristic of any height insulated vertical radiator, TS> with or without typical loading. DK>…How about it, Terry? Can you figure what the field would DK> be like off a 94 kHz loading coil with a top hat? It sure DK> looks to be pretty "standard" in that regard…my first DK> guess says about 1.5 Amps average base current, but 1350 DK> Amps peak base current…what a pulse! TS> Based on 209 ohms and 420 kV, we might expect over 2,000 A at TS> the base. Extrapolating with the ratio of 31.5 and assuming TS> minimal losses, the arc might be around 60 A. That's TS> approaching a gigawatt. TS> As to radiation efficiency, I'd be curious if any data TS> comparable to present day units existed. A 200 ohm base is TS> typical of a 120 degree or so tower. Loading of normal TS> radiators commonly does more to match impedances without TS> higher Q networks, than to boost radiation efficiency. The TS> near zero Vf, and indication (based on what?) of 70 degree TS> wavelength, conflict with normal radiator modelling, as does TS> a VSWR so much greater than 2. TS> I'd be curious, but afraid to even guess. I would speculate TS> that fields from some of the coils might cancel, but that TS> there'd be some radiation from both the long coil, and the TS> arc path. How much I'd guess would depend a lot on TS> construction practices, not shown here. If I had to pick a TS> number to compare with equivalent transmitting power into an TS> efficient radiator, I'd guess this might be similar to around TS> a megawatt, though low duty cycle. Is there any historical TS> field data? The whole idea of the Colorado Springs Experimental Station was to verify Tesla's previously discovered methods of transmitting communications and electrical power without wires. The system was not designed, built, or operated at as radiating transmitter. The Magnifer circuit was operated at industrial power levels to perfect a method of wireless global transmission thru conduction. References to radiation efficiency completely miss the point of the experiment. Tesla stated over and over that his goal was to supress radiation and increase conductivity. This is why the system was required to produce such high voltages. The posted values were derived from only one of many dozens of experiments Tesla performed with the equipment at hand, and is "typical" in showing the type voltages, currents, and frequencies Tesla worked with at the station between 1899-1900. The famous spark photos from the Colorado Springs lab were taken solely to publicize to power processing ability of the machine, and does not document the primary function of the oscillator/coil system. It could also be surmised that spark length gave a good relative indication of system tune given the absence of any reliable commercial diagnostic equipment in 1899-1900. … If all else fails… Throw another Megavolt across it! — Blue Wave/RA v2.12 [NR] * Origin: Cindex Support BBS (314) 837-5422 Florissant, MO. (1:100/395.0) ====================================================================== ===== BBS: WELCOM BBS Date: 07-09-94 (20:55) Number: 12220 From: JAMES MEYER Refer#: NONE To: RICHARD QUICK Recvd: NO Subj: Tesla Capacitors Conf: (111) ELECTRONIC ———————————————————————- —– On 09-06-94, RICHARD QUICK wrote to JAMES MEYER and said: RQ> Please tell me more. What slight modifications would be required, RQ> and how do those modifications reduce or eliminate self- RQ> inductance? RQ> RQ> I am not at all trying to detract from the viability of your RQ> suggestion, which I would like to hear in more detail, but I am RQ> simply trying to outline and clarify some of the problems and RQ> design limitations I have encountered in the course of my RQ> experimentation. An extended foil cap is wound with the foil extended over the edge of the dielectric so that the connection to the foil can be made continuously along the entire edge of the foil. This means that the charging currents are distributed over the foil much more evenly and the effective series inductance is the same as a piece of wire the same length as the cap. Perhaps a picture right now would be worth a thousand more words. "A" "B" ——————————- ^ | dielectric | | r —| ——————————– | o | f | | foil 2 | | l | o | | | | l | i | | | | | l | | | | t | | | | | h | 1 | | | | i | | | | | s —| ——————————– | | "D" | | w ——————————- "C" - a y "A" to "B" is the length of the finished cap. (One foot?) "B" to "C" is the length of the foil before rolling. (Several yards?) The cap is made by laying down one sheet of dielectric of the proper size. Next goes one foil plate placed so that one edge extends past the edge of the dielectric by about a quarter to a half inch. The second dielectric sheet is exactly the same size as the first, and it gets laid down so the corners match the corners of the first. The second foil is the same size as the first and it goes on next, but it is extended to the opposite side as the first foil. Of course you want the dielectric sheets larger than the foil by enough to get the arc-over voltage high enough. Then the cap is rolled up. The two foils will be extended from opposite ends of the cap. It's then only a matter of attaching the two terminals to the foils. Since the entire edge of both foils is available, a good high current connection can be made. If you use a hammer to pound the turns of each foil into contact, you could then solder a real heavy piece of copper strap or a threaded brass rod to the foil at each end. This is how physically small caps with low inductance are made. It's also how the large, pulse discharge, caps in the modulator for the linear particle accelerator at the lab are made. I know. I've dissected a couple after they "blew". You could take apart a few old small caps to get an idea about how they're made. The "orange drop" Sprague caps are usually extended foil. Jim * JABBER v1.2 * The earth is like a tiny grain of sand, only =much= bigger. — FidoPCB v1.5 beta-'j' * Origin: Psychotronic BBS - We are smarter than you. RTP,NC (1:3641/1) ====================================================================== BBS: WELCOM BBS Date: 08-09-94 (07:46) Number: 12237 From: TERRY SMITH Refer#: NONE To: RICHARD QUICK Recvd: NO Subj: Tesla, Col.Sprng Conf: (111) ELECTRONIC ———————————————————————- RQ> Anyway, Terry Smith and Don Kimberlin were commenting on some RQ> info I dug up on Tesla's Colorado Springs Magnifier…. TS> Interesting, yes, but nothing like what would be TS> characteristic of any height insulated vertical radiator, TS> with or without typical loading. DK>…How about it, Terry? Can you figure what the field would DK> be like off a 94 kHz loading coil with a top hat? It sure TS> Based on 209 ohms and 420 kV, we might expect over 2,000 A at TS> the base. Extrapolating with the ratio of 31.5 and assuming TS> minimal losses, the arc might be around 60 A. That's TS> approaching a gigawatt. TS> As to radiation efficiency, I'd be curious if any data TS> comparable to present day units existed. A 200 ohm base is TS> typical of a 120 degree or so tower. Loading of normal TS> number to compare with equivalent transmitting power into an TS> efficient radiator, I'd guess this might be similar to around TS> a megawatt, though low duty cycle. Is there any historical TS> field data? RQ> The whole idea of the Colorado Springs Experimental Station was RQ> to verify Tesla's previously discovered methods of transmitting RQ> communications and electrical power without wires. The system was RQ> not designed, built, or operated at as radiating transmitter. The RQ> References to radiation efficiency completely miss the point of RQ> the experiment. Tesla stated over and over that his goal was to RQ> supress radiation and increase conductivity. This is why the Don and I were simply trying to compare apples and oranges, or place the secondary characteristics of this coil in the realm of references we consider when looking at RF devices of substantial fractional wavelengths. It's normal to look at induced and radiated fields of a broadcast antenna, coupling efficiency to the earth, and the earth resistance in conducting that signal. Tesla's signals obviously have some overlap, though it does appear to be a much different balance of parameters than in intentional RF radiators. You must realize how most components or circuits for one nominal purpose can usually be analyzed as to the (albeit, somtimes minute) elements of other types. For example, you can measure series inductance of many resistors, shunt and series resistance of capacitors, inter winding capacitance and series resistance of inductors, etc. RQ> The famous spark photos from the Colorado Springs lab were taken RQ> solely to publicize to power processing ability of the machine, RQ> and does not document the primary function of the oscillator/coil RQ> system. It could also be surmised that spark length gave a good RQ> relative indication of system tune given the absence of any RQ> reliable commercial diagnostic equipment in 1899-1900. Ahh, you're just jealous that with modern technology, you haven't been able to build something twice as large. «g» Terry — Maximus 2.01wb * Origin: Charges filed under Ohms Law! (203)732-0575 BBS (1:141/1275) ====================================================================== BBS: WELCOM BBS Date: 09-09-94 (11:19) Number: 12267 From: DON KIMBERLIN Refer#: NONE To: RICHARD QUICK Recvd: NO Subj: Tesla, Col.Sprng Conf: (111) ELECTRONIC ———————————————————————- <Terry Smith posted:> RQ>TS> I'd be curious, but afraid to even guess. I would speculate RQ>TS> that fields from some of the coils might cancel, but that RQ>TS> there'd be some radiation from both the long coil, and the RQ>TS> arc path. How much I'd guess would depend a lot on RQ>TS> construction practices, not shown here. If I had to pick a RQ>TS> number to compare with equivalent transmitting power into an RQ>TS> efficient radiator, I'd guess this might be similar to around RQ>TS> a megawatt, though low duty cycle. Is there any historical RQ>TS> field data? RQ>The whole idea of the Colorado Springs Experimental Station was RQ>to verify Tesla's previously discovered methods of transmitting RQ>communications and electrical power without wires. The system was RQ>not designed, built, or operated at as radiating transmitter. The RQ>Magnifer circuit was operated at industrial power levels to RQ>perfect a method of wireless global transmission thru conduction. SET MENTAL_BLOCK.SYS /on …Oh, boy, do I have trouble with that, Richard. As you note, "radiation" does imply propagation of magnetic or static fields through space. But "conduction" implies propagation of induction fields through the earth. Then, we have some sort of Tesla experiments involving what has to be radiating X-rays and such toward the ionosphere. …Please sort out my feeble mind. While I have no problem with understanding Tesla could have been working on both radiation and conduction as I know them, it seems like the descriptions don't separate the two…unless there is some higher plane of understanding I need to get to. (Yes, the two are related, but usually we're concentrating on one and trying to suppress the other…) RQ>References to radiation efficiency completely miss the point of RQ>the experiment. Tesla stated over and over that his goal was to RQ>supress radiation and increase conductivity. This is why the RQ>system was required to produce such high voltages. …Again, when it's conduction, the emphasis is on current, not voltage…at least for ordinary mentalities…can you help get my perspective right for this understanding? — GOMail v2.0j Beta [94-0035] * Origin: Borderline! BBS Kannapolis, N.C. (1:379/37) ====================================================================== ===== BBS: WELCOM BBS Date: 11-09-94 (13:10) Number: 12291 From: BRETT LILLEY Refer#: NONE To: RICHARD QUICK Recvd: NO Subj: Tesla Capacitors Conf: (111) ELECTRONIC ———————————————————————- —– Hi Richard, I have followed the Teslar thread here with interest even to the cost of obtaining copies of your videos via Jim Oliver. They are most impressive although I make a plea no doubt endorsed by other viewers, PLEASE INVEST IN A TRIPOD FOR YOUR CAMERA. I get sea sick watching them :-( I have around 15 years experience in radio, mostly at VHF and UHF and Microwaves but my training included the LF, MF and HF bands. Your Tesla coils operate at the lower end of the LF bands. > RQ> Flat plate caps have no inductance. Wrong! all capacitors have inductance as well as series and shunt resistance and of course capacitance. It is just that flat plate caps have much less inductance and at LF frequencies it provides insignificant reactance. However even at LF frequencies an effect known as Skin effect can result in a significant effective series resistance, more about that later. > RQ> Rolled caps contain two > RQ> or more plates which are tightly rolled up. Rolled plates > RQ> exhibit some properties of coils, They are coils! > RQ> they contain a certain degree of self-inductance. Not surprising, Knowing their capacitance and self resonant frequency you should be able to calculate their inductance. fc = 1/(2*pi*(L*C)^-2) or L = 1/((2*pi*fc)^2*C) > JM> Rolled caps don't always have to show a lot of inductance. > JM> With a slight modification to your construction techniques, > JM> you could make "extended foil" caps with almost no > JM> inductance. The inductance of an extended foil cap doesn't > JM> change as they get bigger either. > Please tell me more. What slight modifications would be required, > and how do those modifications reduce or eliminate self- > inductance? One method would be to terminate each plate at its edge rather than its ends by extending the edge of one plate beyound the insulator at one end of the roll and doing the same with the other plate at the other end. You could then bond across all the turns of each plate. This would reduce the inductance (and the series resistance!) by making the effective length of conductor the width of the plate rather than the length of the plate. You would of course have to double the "creepage" allowance of insulator at the edges of the plates (ends of the roll). > The second design limitation I have encountered is a lowering of > the tank circuit Q factor when larger rolled caps are used in the > oscillator. I attribute part of this to destructive self-reson- > ance, but this can be controlled/reduced by operating the > oscillator at lower frequencies, and maintaining a suitable > spread between the self-resonate frequency of the cap, and the > normal operating frequency of the oscillator. The destructive > interference does not seem to account for the large drop in Q > factor I read on my scope. You are encountering skin effect. At frequencies higher than about 100khz current flow in a conductor only occurs near the surface thus reducing the effective cross sectional area and increasing the effective series resistance. This effect will occur in all parts of your primary tank circuits and in the secondary coil. The usual method of countering this is to use conductors with a large surface area for a given cross section. Ie. compare the surface area per unit length of a flat conductor vs a round conductor of the same cross sectional area. Other techniques effective at LF include the use of a multi stranded conductor where each strand is insulated (Litz wire). I definately don't proffess any experience in the area of Tesla coils but hopethat a little cross pollenation with radio theory will help eliminate some of your problems. Bye. — * Origin: Brett's Point (Co-Sysop of The Beast - 64 7 3575355) (3:774/600.4) ====================================================================== BBS: WELCOM BBS Date: 19-09-94 (16:12) Number: 12788 From: RICHARD QUICK Refer#: NONE To: DON KIMBERLIN Recvd: NO Subj: Tesla, Col.Sprng Conf: (111) ELECTRONIC ———————————————————————- RQ>The whole idea of the Colorado Springs Experimental Station RQ>was to verify Tesla's previously discovered methods of RQ>transmitting communications and electrical power without RQ>wires. The system was not designed, built, or operated at as RQ>radiating transmitter. The Magnifier circuit was operated at RQ>industrial power levels to perfect a method of wireless RQ>global transmission thru conduction…. … RQ>The high voltage and RF frequencies means that large amounts RQ>of energy can be conducted freely through low pressure gas RQ>(a-la waveguide) where there is no radiating wave propagation. DK> …Hmmm…I'm right with you fine up to this point, but it DK> sure seems that "conduction channel" would have to be focused DK> toward the ionosphere somehow… I am not sure that Tesla was aware of the existance of the ionosphere, nor that it matters much. Practical lab experiments of scale test systems can be performed by any coiler worth his salt. A four inch diameter coil (transmitter) and a six inch diameter coil (receiver) can be set up in transmitter/receiver configuration. The four inch coil is heavily top loaded with capacitive air terminal (toroid) to prevent spark breakout. Top loading the four inch coil will also reduce to coil resonate frequency to the point where a frequency match can be made with the unloaded, or slightly loaded, six inch coil. I connect the base of the two coils to a common ground, and run an 8 foot long florescent tube, or two tubes with the ends pressed and taped together between the two air terminals of the coils. Real power can be transmitted through the tube. I have no problems pumping through a killowatt or two. At a threshold voltage, which depends on gas pressure and composition, the low pressure gas becomes self ionizing, and conducting. DK> … and I don't know of any focusing devices Tesla used for DK> that…otherwise, I'm right here with you – I think… I am afraid I cannot give a precise answer to this question of beam focusing devices. Alas there are acknowledged holes in the documentation of Tesla's advanced work. Many of these gaps were deliberate on Tesla's part to throw off the competition. Yet we get closer and closer every year. Serious study, and experi- mentation, leads us to bridges over these gaps. In all of the work I have personally conducted, I have found no flaws in Tesla's basic logic. DK> …Was the Magnifier a focusing device for the conductive DK> beam? No, the Magnifier is a name for a specific three coil arrangement which represents a power processing efficiency breakthrough. Tesla always strove for high efficiency, and the Magnifier gave it to him in a RF resonate tuned transformer of enormous power. DK> …But, now that we have it going up, how do we tap into it DK> to get it down? I would have to assume that the receiver plugged in the same way as the transmitter. An interesting thing about this system is that it uses a resonator for the final stage to deliver the high EMF output. In the same simplified scale experiment I briefly described above, the receiving coil is still processing energy even if the conductive channel (low pressure tube) is not connecting the air terminals. A "free" (not inductively coupled to the transmitter system) resonator will pick up and resonate on ground current alone. No air terminal conductive channel is required for the system to deliver some considerable energy to the receiver through ground conduction alone. Enough voltage is present on the air terminal of the receiving coil to cause it to spark freely, light bulbs, etc.. I have gotten bulbs to light on a tuned receiving coil 1/4 mile away from a shielded transmitter. The input energy to the transmitter was only one killowatt, there was no raditaion: the "pickup" or receiving coil was connected to a 50' length of aluminum flashing sunk in creek bottom. There are some interesting properties to Tesla's open ended resonators. It appears that a large scale system would deliver enough energy from the ground connection alone to open up a conductive channel to the stratosphere (via X-Ray, UV bulbs on the air terminal of the receiver). … If all else fails… Throw another Megavolt across it! — Blue Wave/RA v2.12 [NR] * Origin: Cindex Support BBS (314) 837-5422 Florissant, MO.

/data/webs/external/dokuwiki/data/pages/archive/science/rqmsgs_t.txt · Last modified: 2001/11/04 05:40 (external edit)