Philips 202P70/00 Service Manual page 31

B. Video
Repair Flow
1. Symptom:
(with white pattern)
no picture
green LED on
2. Symptom:
no video (or dim)
only raster with/without retrace line
green LED on
3. Symptom:
no OSD or
OSD out of Sync.
Repair Flow Chart (Continued)
Rough check for R, G, B
1. Video input=0.7V
2. 7701 Video output=3.4V
3. Video output>35V
Check hearter
Check
=+6.3V
EHT=25KV
Check HUNLOCK
7421 Pin17
Check Vg1
Vg1=-30V
H.V. Check 7701
Check
OK
VG1<-150V
OK
Turn down Vg2
NO
Check 7701
Pin 6, 8, 10
input swing
OK
Replace 7701
202P7 CRT
Go to cover page
Check
R, G, B output
NO
30<2706<80
30<2726<80
30<2746<80
OK
Check
VG2>450V
Check cathode
+83V
Check 7701
Pin 16, 19, 22
output swing
31