U2000 Dim picture (AGAIN!)

LyonsArcade

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I've read a lot about U2000 boards and how they give a dim picture sometimes, and that can sometimes be fixed by resistor 811. Well, I pulled all the specs for it and on a U5000, that resistor is a 100K ohm. I tested mine, and sure enough, it was open. So I put another 100K ohm resistor in there, and got the colors back that I was missing, and the screen is a bit brighter, but still dim.

When I looked it up on a U2000 schematic just to make sure, it calls for a 75K ohm resistor at 811. So, I replaced the 100k with a 75k, and it made the screen a bit brighter. It's still not good enough though, not even close.. you can turn the brightness up but it washes the screen with white. I've tried 100's of settings with the brightness/contrast/screen and 5 color adjustments, but can't get a good vivid picture. It seems like it's a contrast issue, you can get a good 'black' and color mix, but the screen is dull looking.

I found something on wells garner's site and they pointed at 811, R310, and R823. All of those are in spec now. I capkitted the monitor too, btw.

In the test menu, I seem to get a pretty good 'red' 'blue' and 'green' solid screen, but on the color bars it doesn't look as good. Also if I put another jamma board in, It's still too dim.

Anybody have any other ideas? I don't think it's the tube, because you can get a nice bright image on it, it's just washed out in white. It's like I can't get a good contrast. The contrast is jacked all the way up and the pot is good.
 
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