Abnormal Display - ViewSonic E90fB-4 Service Manual

6-2-1.NO SIGNAL ON SCREEN
CHECK VIDEO IC801 VCC ABOUT 5V
CHECK THE OUTPUT VOLTAGE
OF IC801 PIN 19, 20, 21 ABOUT 3Vpp
CHECK THE VOLTAGE OF
VIDEO AMP ABOUT 80V
CHECK THE VOLTAGE OF CRT
CATHODE ABOUT 40Vpp
CHECK THE VOLTAGE OF FBT SCREEN
ABOUT 400V TO 700V
ViewSonic Corporation

6-2 ABNORMAL DISPLAY

NG
OK
NG
OK
NG
OK
NG
OK
LESS THAN 400V
EXCEED 700V
19
CHECK THE 5V PIN
OF P802 CONNECTOR
CHECK THE RELATIVE CIRCUIT
OF IC801 PIN 10/PIN 18 Vcc CIRCUIT
CHECK THE 80V RELATIVE CIRCUIT
ON MAIN PCB
CHECK THE IC802
RELATIVE CIRCUIT
CHECK FBT RELATIVE CIRCUIT
CHECK FBT & CRT RELATIVE
CIRCUIT OR REFER ITEM 6-1
Confidential-Do Not Copy
E90fB-4