Abnormal Display - Tatung VM5ERDA Service Manual

1.NO SIGNAL ON SCREEN
CHECK VIDEO IC VCC ABOUT 8V
OK
CHECK THE OUTPUT VOLTAGE
OF IC801 PIN 13, 15, 18 ABOUT 3Vpp
OK
CHECK THE B+ VOLTAGE OF
VIDEO PCB ABOUT 75V
OK
CHECK THE VOLTAGE OF CRT
CATHODE ABOUT 40Vpp
OK
CHECK THE VOLTAGE OF FBT SCREEN
ABOUT 400 TO 600V

6-2 ABNORMAL DISPLAY

NG
NG
NG
NG
LESS THAN 400V
EXCEED 600V
CHECK THE 12V PIN
OF P802 CONNECTOR
CHECK THE RELATIVE CIRCUIT
OF IC801
CHECK THE 80V RELATIVE CIRCUIT
OF SMPS ON MAIN PCB
CHECK THE IC802
RELATIVE CIRCUIT
CHECK FBT RELATIVE CIRCUIT
CHECK CRT RELATIVE CIRCUIT
OR REFER ITEM 6-1