45
V50 109B5
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Repair Flow Chart (Continued)
B. Video
Repair Flow
check 7301
pin11 HFLB
1.Symptom :
(with white pattern)
no picture
green LED on
check
EHT=26KV
+/-0.2kV
rough check for R, G, B
1. video input= 0.7V
2. 7301video output =2.5V
3. 7701 video output > 35V swing
check 7301
pin5 CLBL
check DC restoration
7722,7732,7752
7721,7731,7751
check 7301 pin24
2V< ABL < 5V
check 7301
pin 6,8,10
input swing
check 7701
pin6,7,9
input swing
Ok
replace 7701
Ok
replace IF
cable
No
replace 7301
check
VG1 < -150V
Ok
No
check blanking
7501 pin17
check heater
=+6.3V
Ok
check
R,G,B output
30<2725<80
30<2733<80
30<2753<80
Ok
2.Symptom :
no video (or dim),
only raster with/without retrace line
green LED on
check Vg1
Vg1 = 0V
check cathod
+83V/+190V
Ok
check blanking
7501 pin16
No
turn down Vg2
check 7701
pin 1,2, 3
output swing
check
7304 pin10
VFLB
3. Sympton :
no OSD or
OSD out of sync.
check 7301
pin 2,3,4 input
check
7301 pin1
check 7304
pin2 VCO
pin3 RP
check 7304
pin5 HFLB
replace 7301
Ok
No
replace 7304
No
check 7304
pin 7,8(IIC)
check
7501 pin16
Ok
No
check
VG2 > 350V
Ok
No
check
7304 pin12
Ok
Содержание V50 109B5
Страница 7: ...9 Go to cover page 7 V500 109B5 Wiring Diagram ...
Страница 25: ...C B A Of Video Board 25 9 Go to cover page V50 109B5 ...
Страница 29: ...C B A Of Main Board 29 9 Go to cover page V50 109B5 ...
Страница 30: ...30 V50 109B5 9 Go to cover page C B A Of Main Board ...
Страница 34: ...34 V50 109B5 Control Panel board C B A 9 Go to cover page ...
Страница 36: ...36 V50 109B5 MHR board C B A 9 Go to cover page ...