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Main => Monitor/Video Forum => Topic started by: castlesteve on June 11, 2008, 07:22:16 am

Title: k7401 horizontal offset problem
Post by: castlesteve on June 11, 2008, 07:22:16 am

I have fixed quite a few of these 7401s, but this problem is confusing me :dunno.

The picture is fine, but is pushed off to the right about 3 inches.  No amount of horizontal position change will fix it.  If I adjust the horizontal sync POT, I can get it to normal size, but then the images becomes erratic.

I've replaced the:
* all caps and any cold solder joints (no change)
* tried a new tube/yoke (no change)
* replaced neck board (no change)
* replaced remote control board (no change)
* replaced U701 (no change)

Only thing left I can see is q800, but no one ever talks about that guy.

UPDATE - I replaced q800... no change.  Maybe I have some random resistor that went down around the horiz sync/size area.   

Any other suggestions?

Title: Re: k7401 horizontal offset problem
Post by: Ken Layton on June 11, 2008, 10:24:32 am

Sounds like you may need to telephone Welss-Gardner tech support.