Sony Trinitron KV-21V4A Service Manual page 49

3-2. SYSTEM CONTROL-SERVO PERIPHERAL CIRCUIT INTERFACE (MA BOARD IC501)
Signal Pin No. I/O
REC CTL IC501 O
O
CAP STOP IC501
(O.D)
STEP PLS IC501 O
CTL REC IC501 O
CTL INDEX IC501 O
PB CTL IC501 I
DRUM PG IC501 I
DRUM FG IC501 I
CAP FG IC501 I
CAP DA IC501 O
DRUM DA IC501 O
CTL STEP IC501 O
*1. 25Hz pulse.
*2. Pulse in tape running.
*3. Reverse logic pulse of STEP PLS.
*4. "L" when drum rotation stops.
*5. Unstable period pulse.
*6. Pulse of period proportionate to tape speed.
*7. 25Hz pulse.
*8. 300Hz pulse.
*9. Pulse in tape running.
*10. Approx. 2 msec. period "H" or "L" pulse.
*11. Approx. 1.5 msec. period "H" or "L" pulse.
*12. Approx. 3 msec. period "H" or "L" pulse.
*13. "H" in FWD direction and STEP drive.
TAPE
STOP FF REW THREADING UNTHREADING
*1 *1 *1 *1
HI-Z HI-Z HI-Z
L
(O.D) (O.D) (O.D)
L L L L
L L L L
L L L L
H *6 *6
*4 *7 *7 *5
*4 *8 *8 *5
H/L *6 *6 *5
*10 *10 *10 *10
*12 *12 *12 *12
L L L L
TAPE PB ·
PB PAUSE SLOW
*1 *1 *1 *1
HI-Z HI-Z
L *3
(O.D) (O.D)
L L L *2
L L L L
L L L L
*1 H/L *2
*5 *7 *7 *7
*5 *8 *8 *8
*5 *6 H/L *9
*10 *11 *10 *10
*12 *12 *12 *12
L L L *13
PICTURE SEARCH
X2 CUE REVIEW REC PAUSE WRT/ERS
*1 *1 *1 *1
HI-Z HI-Z HI-Z HI-Z
(O.D) (O.D) (O.D) (O.D)
L L L L
L L L H
L L L L
*6 *6 *6 *1
*7 *7 *7 *7
*8 *8 *8 *8
*6 *6 *6 *6
*11 *11 *11 *11
*12 *12 *12 *12
L L L L
REC · PB INDEX
*1
HI-Z
(O.D)
L
L H
L H
H
*7
*8
H/L
*10
*12
L