6-11
7. Checking the interface circuit of sync signal
7.1 Checking the control circuit of horizontal sync pulse
7.2 Checking the control circuit of vertical sync pulse
OK
NG
Check the horizontal sync signal on I306 pin 150 TTL level.
Process "Checking the resolution change IC movement" section.
Failure point
1) Video cable may have failed.
2) Printed wire broke between P302 pin 13 and I306 pin 150.
3) FB302, R332 open.
OK
NG
Check the vertical sync signal on I306 pin 148 TTL level.
Process "Checking the resolution change IC movement" section.
Failure point
1) Video cable may have failed.
2) Printed wire broke between P302 pin 14 and I306 pin 148.
3) FB301, R328 open.