There is a -5v test point not far from the pot. When one of mine was doing this, I found that the -5v rail would jump around when the screen was playing up. The -5v is voltage divided by the pot so if it is low to start with, the pot just makes it worse. For me, it eventually turned out to be one or both of the diodes between the transformer and the -5v test point. I’ve replaced the diodes and haven’t seen any issues since, however that could also just be coincidence! YMMV
Next, I have a m100 with a very faint screen. Originally the screen flickered bright dark randomly like as if the contrast pot was bad. So I shot the contrast pot with DeoxIT D5, and the the screen went almost out. It's not dead, just extremely faint. You can only see any contrast at an extreme shallow angle. This was a few days ago. It got a little better after a day, but then doesn't seem to be getting any further better since then. Is there a test point I can check or something to correct a voltage level? Should I wash that pot with some other product? I know there is a version of deoxit that says it's for faders, maybe that? Or Alcohol to dry it all out? (but then what do I put back in since you don't want to operate it dry very much?) -- bkw
