ViewSonic G90fB-4 - Video and Blanking Issues

6-3. Abnormal video level on screen
NG
OK
NG
OK
NG
OK
NG
OK
6-4. No blanking
N
G
O
K
CHECK THE RELATIVE
CIRCUIT OF BLANKING
CHECK THE RELATIVE CIRCUIT
CHECK G1 RELATIVE CIRCUIT
CHECK R821 ON VIDEO PCB,
FBT PIN 5 ON MAIN PCB
OF FBT
CHECK THE VOLTAGE AT
PIN10/14/17/22 OF IC801 ABOUT 5V
CHECK 5V SUPPLY CIRCUIT
CHECK THE SIGNAL OUT ABOUT 0.7VP-P
CHECK SIGNAL CABLE O
R
INTERFACE CARD
CHECK THE CLAMP PULSE OF IC801 PIN27
CHECK THE RELATIVE CIRCUIT
OF IC801 PIN27
CHECK THE VOLTAGE OF IC801
PIN23/24/25 ABOUT 4VP-P
CHECK THE RELATIVE CIRCUIT
OF IC801 PIN23/25/24 OR THE
IC801 FAIL
CHECK THE RELATIVE CIRCUIT OF IC802
ViewSonic Corporation Confidential - Do Not Copy G90fB-4
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