14
6.TROUBLE SHOOTING CHART
6-1 NO RASTER, CRT RELATIVE CIRCUIT PROBLEMS
REFER ITEM S.M.P.S.
BRIGHTNESS SET TO MAX. THEN
CHECK CRT G1 VOLTAGE
NG
NG
NG
NG
NG
OK
OK
OK
OK
OK
CHECK THE HIGE VOLTAGE
CHECK THE VOLTAGE OF CRT
HEATER ABOUT 6.3V
CHECK VOLTAGE OF THE CRT
CHECK BRIGHTNESS CIRCUIT
OK
CHECK POWER SAVING CIRCUIT,
"ABNORMAL DISPLAY"
H-SYNC, V-SYNC SIGNAL
CHECK SCREEN VOLTAGE ABOUT
LESS THAN 300V
CHECK FBT
CHECK MAIN PCB POWER SUPPLY
CHECK FAILSAFE CKT IC401
Q909, Q910
CHECK CRT'S HEATER RELATIVE
CIRCUIT Q907, Q908
Q703, Q704, Q705 RELATIVE CKT.
PIN 25 RELATIVE CKT.
OF CRT ABOUT 24.5 ~ 25.5KV
400V TO 600V
REFER ITEM 6-2
53V, 14V, 78V
CATHODE ABOUT 55V TO 65V
CHECK MAIN PCB POWER
SUPPLY 47.0V,13V
CHECK THE HIGE VOLTAGE OF
CRT ABOUT 23~24KV
CHECK BRIGHTNESS CIRCUIT
Q705 RELATIVE CKT.
Содержание v7650
Страница 16: ...15 2 ABNORMAL VIDEO LEVEL ON SCREEN 3 ABNORMAL DDC PLUG PLAY ...
Страница 17: ...16 6 2 ABNORMAL DISPLAY 1 NO SIGNAL ON SCREEN ...
Страница 18: ...17 6 3 NO BLANKING 6 4 HOR OSC DEF HV CIRCUIT FAULT 1 NO RASTER DISCONNECT WITH SIGNAL CABLE ...
Страница 22: ...21 7 MECHANICAL OF CABINET FRONT DIS ASSEMBLY ...
Страница 40: ...39 9 BLOCK DIAGRAM ...
Страница 41: ...40 9 1 BLOCK DIAGRAM SMPS ...
Страница 43: ...42 IC401 STV9118 IC803 LM2480NA ...
Страница 44: ...43 ...
Страница 45: ...44 ...
Страница 46: ...45 11 PCB LAYOUT 11 1 Main Board ...
Страница 47: ...46 11 2 Video Board ...