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Monitor Repair Log and Database. **Arcade and Gaming** => Monitor Repair Tech Support => Topic started by: badbaud on July 19, 2013, 02:07:25 AM



Title: Tatung VS14228T retrace lines
Post by: badbaud on July 19, 2013, 02:07:25 AM
This is the one that has the power supply located inside a metal cage which is mounted above the board and the neck board has transistors but no IC.

Did a complete cap job, all electrolytics replaced.

Replaced H and V transistors on input.

Replaced vertical amp and H/V IC.

Still get retrace lined from the middle of the screen to the top of the screen.

All I have is a blurry schematic to work with and can't figure out how blanking is developed in the circuit.

Any help would be appreciated.


Title: Re: Tatung VS14228T retrace lines
Post by: montech on September 12, 2013, 07:16:21 PM
Check R720 off pin 10 and 12 0f the LA7837. Its a weird value like 140 ohms at 2 watts, I have seen them go way up and cause this problem.


Title: Re: Tatung VS14228T retrace lines
Post by: badbaud on September 12, 2013, 08:59:20 PM
Thanks! I'll give that a try and let you know.