6.TROUBLE SHOOTING CHART
6-1 NO RASTER, CRT RELATIVE CIRCUIT PROBLEMS
1.ABNORMAL POWER SUPPLY
90V,12V
CHECK MAIN PC BOARD
NG
OK
CHECK THE HIGE VOLTAGE OF CRT ABOUT 23.5 ~ 25.5KV
CHECK POWER SAVING CIRCUIT Q909,Q910
NG
OK
CHECK THE VOLTAGE OF CRT HEATER ABOUT 6.3V
NG
OK
CHECK SCREEN VOLTAGE ABOUT 400V TO 600V
LESS THAN 300V
OK
BRIGHTNESS SET TO MAX. THEN CHECK CRT G1 VOLTAGE
NG
CHECK FAILSAFE CKT Q402,Q403
RELATIVE CKT.
CHECK CRT’S HEATER RELATIVE CIRCUIT Q907,Q908
CHECK FBT. D706,R723,C713
CHECK BRIGHTNESS CIRCUIT Q703,Q704,Q705 RELATIVE CKT.
OK
CHECK VOLTAGE OF THE CRT
CATHODE ABOUT 60V TO 70V
|
|
|
|
NG |
|
| REFER ITEM |
|
| “ABNORMAL DISPLAY” | |
| |||
|
|
|
|