We have major a breakthrough!
So I replaced UJ2, UJ3, UJ4, let the board soak in vinegar for a couple of hours, rinsed it in soapy water and then let it dry over the evening and night.
When I just powered it on there was a
normal chime (not as loud as the chimes of death I had a week ago), but still the same horizontal bars. I restarted it a few times and sound was gone again, and horizontal bars every time. Then I remembered that I forgot to put the video ROM back after cleaning... Now:
So the two obvious issues right now:
- sound. Only twice have I heard the startup chime, otherwise sound is dead. Also on the headphone jack.
- the display has issues. It's very dark, and I don't know if you can see it on the picture, but there's some lighter "shadowing" to the right of black pixels.
Any advice where to start troubleshoot these issues? I can try to adjust the brightness trim pot on the analog board, I just need to get a proper tool first. I guess the analog board needs a re-cap too... I'm not just that comfortable yet with CRT discharging and handling the high voltage side of things.