-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
LINE SIGNALS IN CCITT SYSTEMS
-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
You will be given an entry followed
by 4 pieces of information on that en- try. The titles for those 4 pieces of information are: Direction, CCITT #3 (1VF), CCITT #4 (2VF), and CCITT #5 (2 VF). The individual pieces of infor- mation will be, for the most part, ab- breviated to the use of symbols, the symbols table will follow the entries at the end of this section.
SEIZE TERMINAL: –>,X,PX,X
SEIZE TRANSIT: –>,N/A,PY,N/A
START PULSING-TERMINAL: ←-,X,X,Y
START PULSING-TRANSIT: ←-,N/A,Y,N/A
END OF PULSING (ST)*: –>,250MS,xSxSxS x,1500+1700HZ
BUSY: ←-,XX,PX,Y
ACKNOWLEDGE: –>,N/A,N/A,X
ANSWER: ←-,XSX,PY,X
CLEAR BACK (ON HOOK): ←-,XX,PX,Y
RING FORWARD: –>,XSX,PYY,Y(850+OR-200 MS)
CLEAR FORWARD (DISCONNECT): –>,XXSXX, PXX,X+Y
DISCONNECT ACKNOWLEDGE: ←-,XXSXX,PYY, X+
SYMBOL TABLE
X = 2280+OR-6HZ,120+OR-30MS
XX = 2280+OR-6HZ,600+OR-120MS
S=100+OR-20MS SILENCE
←- OR –> = DIRECTION
Those were for CCITT #3 (1VF) (Second item after each signal)
X = 2040+OR-6HZ,100+OR-20MS
Y = 2400+OR-6HZ,100+OR-20MS
XX = 350+OR-70MS
YY = 350+OR-70MS
S = 35+OR-7MS;x:2040HZ,35MS
P = (2040HZ,2400HZ),150+30MS
Those were for CCITT #4 (2VF)
X = 2400+OR-6HZ
Y = 2600+OR-6HZ
Those were for CCITT #5 (2VF)
N/A = Not Applicable
* = Combination #15 of Address Code
Downloaded from Strictly Business (415) 583-1673. Press a key… a