greenish black level
 

Hmm, this is an odd trend.

when on a black screen, the faint black screen has a greenish tint to it.. if I raise the brightness, it turns to a neutral grey, like it should be.



Let me guess, tired CRT.?

If I adjust the color controls on the mainboard, I can get the black level neutral, but then the color dark grey is affected.

The CRT is not tracking uniformly over the brightness range, thus showing some age. The best thing to do is touch up the screens/gains for best grey scale in the range of brightness that is normal. The less you overdrive, the better your chances are for extending it's life.

CRT's can vary a bit and still be considered acceptable, it's just one of those things you monitor over time to see if the trend gets worse.

Ok. I attempted to modify the levels, the green pot is getting quite touchy I'm noticing.. I was able to get it adjusted so black appears like it should.

Doesn't seem to have affected the greys at all, which is good.