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Troubleshooting
MD 1998LE (B1997PNST)
5-3 Vertical Scan (Raster is one horizontal line)
Replace I301.
Check pin 12 & pin
13 waveform at
I401
Yes
Check voltage of
pin 3 at I301
(about 17.3 V)
Check
pin 4 or pin 7 waveform
at I301
Vertical Scan Abnormal
Abnormal
Normal
No
OK
Replace I301
Check R307 short ?
Still no vertical scan
Check or replace CRT
Yes
Replace R307