1.3 No Picture

1) AV board

1. Check that the Vcc-voltages(+5V, -5V) are applied to AV circuits.
Pins 47-50 of K10A, Pins 47-54 of K10B ..............5V
Pins 39-42 of K10B..............................................-5V
Check IC1001, IC1002 and IC1021.
2. Check that the following input signals are observed correctly.

2) Main board

1. Check the signals at following test points.
Video signal at TP208, TP218
V-sync signal at TP7224
H-sync signal at TP7223
2. Check that the PC/AV switching signal is correct.
Pin 16 of IC5201 .................................................AV: H, PC: L
Pin 5 of IC5282....................................................AV: H, PC: L
3. Check that the RGB signals are observed at following test points.
TP211, TP221R, TP2211R....................................R-signal
TP212, TP221G, TP2221G....................................G-signal
TP213, TP221B, TP2231B....................................B-signal
4. Check that the signals are observed at following test points.
TPDHS, TP3322...................................................V-Sync,
TPDVS, TP3321 ...................................................H-Sync
5. Check that the S/H signals are observed at following test points.
TP501, TP511 ......................................................R-signal
TP531, TP512 ......................................................G-signal
TP561, TP513 ......................................................B-signal
6. Check that the NRS signals are observed at test points TP3581 and TP3582.
Part 4: Troubleshooting

4-7

SIGNAL K10A-pin No. K50A-pin No.
V-Sync 17-18 17-18
H-Sync 15-16 15-16
B 11-12 11-12
G 9-10 9-10
R 7-8 7-8
Video 33-34 33-34
S-C 29-30 29-30
S-Y 25-26 25-26