Samsung HP-R5052 Service Manual page 114

Circuit Description
■ Troubleshooting the Drive Board
1) Y Buffer
- To check whether the Y Main board is properly working, check the operation of the Y Buffer first.
- Separate the connector of the Y Buffer from the Y Main board.
- Check OUTL and OUTH and confirm that the forward voltage reduction is between 0.4V ~ 0.5V.
UP - CN5407 1~10pin - OUTH / 11~33pin - OUTL
LOW - CN5507 50~41pin - OUTH / 40~17pin - OUTL
- In addition, the resistance between the points must be higher than a few kΩ .
13-22
OUTL
OUTL
OUTH
<Y buffer U P>
OUTH
OUTL
OUTH
<Y buffer LOW>
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