Maker Pro
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Viewsonic G790 compressed horizontal

J

James Sweet

Jan 1, 1970
0
I posted about this a while back and got a few tips but now I'm giving it a
second attempt. HV and video is working fine, but the horizontal (separate
H-drive circuit) has a problem. The image is compressed to a vertical strip
about 2" wide. I managed to get it apart to a point where I can access the
bottom of the board with the monitor running but now I'm a little confused
trying to follow the traces and figure out where B+ is coming from. Does
anyone know what value I should see when measuring from the side of the
H-yoke opposite the deflection transistor? Also I'm assuming that the
transistor must be fine since I have some deflection, I've only ever seen
them fail totally shorted or open junction. I did test it on 12v with a
small incandescent lamp and while the lamp glows constantly (damper?) it
does get brighter when I apply a small current to the Base. I'm at a point
where I need another hint to get me going on this thing.
 
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