Page 10
Trouble Shooting
NEC-FA150ATUA
8. Checking the interface circuit of sync signal
8.1 Checking the control circuit of horizontal sync pulse
Check the horizontal sync signal on
I306 pin 19 and I305 pin 127 (HS_ASIC at
TTL level.)
O K
N G
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 I302 pin 13.
3) FB323, R302 open
Process "Checking I302 pin 8 Output at TTL level
O K
N G
Process "Checking I302 pin 13 Input at TTL level
O K
N G
Failure point
1) Printed wire broke between I302 pin 8 and
I306 pin 19 I305 pin 127
2) FB305 open
Failure point
I302 failure