[Dubis7]

They existed, but have changed, if that makes sense. When I started, the set had AC hum in the audio from bad electrolytics. The picture would shrink and change size with brightness, and the vertical hold was exceptionally touchy. I was also noticing some flashing on the screen. I'm not sure how to describe it, almost like WWII era flak, if you've ever seen video of that. With the brightness up it looked more like the flickering lines you get with tracking issues on a VCR, but with the brightness down they'd be more visible. That wouldn't start until the set had been on for awhile, though.

Since replacing C1 and C2, plus the two paper caps on the main board, the vertical and horizontal hold is much better and the audio hum is gone, but the picture shrinkage and growth is much worse, and I'm hearing sparking from around the flyback. I can't seem to find exactly where it's coming from, though, and I'm not seeing any parts actually failing. I ended up leaving it on for awhile and despite all the sparking noises nothing actually stopped working. It has developed that ringing that I posted earlier, that's new as of last night (and didn't start until quite awhile after replacing C1 and C2.)

I'm wondering if I don't have a problem with the HV rectifier. I ordered a spare to see if that changes anything. I know I have HV from the flyback, since bringing a screwdriver near it and the cap to the HV rectifier causes it to send a healthy spark, so I'm personally inclined to think that the flyback itself is fine.

Any other thoughts? Could this be a yoke problem?