Checking The Interface Circuit Of Sync Signal; Checking The Control Circuit Of Horizontal Sync Pulse; Checking The Control Circuit Of Vertical Sync Pulse - Acer AL1702 Service Manual

7. Checking the interface circuit of sync signal

7.1 Checking the control circuit of horizontal sync pluse
Check the horizontal sync signal on P302 pin3 TTL
Check the horizontal sync signal on I305 pin37 TTL
Failure Point
Process "Checking the resolution change IC
movement" section.
7.2 Checking the control circuit of vertical sync pluse
Check the horizontal sync signal on P302 pin2 TTL
Check the horizontal sync signal on I305 pin36 TTL
Failure Point
Process "Checking the resolution change IC
movement" section.
level.
NG
OK
level.
NG
OK
level.
NG
OK
level.
NG
OK
Failure Point
Video cable is failure.
Failure Point
1) Printed wire broke between P302 pin3 and
I305 pin37.
2) FB313, R329 open.
3) R331, C346 short.
Failure Point
Video cable is failure.
Failure Point
1) Printed wire broke between P302 pin3 and
I305 pin36.
2) FB312, R328 open.
3) R330, C345 short.
AL1702
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