Okay, well, I'm back with a new problem.
After using this without problem for a few months, I suddenly starting having some bizarre intermittent issues with the picture and audio. It would run fine for awhile, then suddenly the entire set would have this dip where the picture would become blurry and dim and the audio would hum, and then it would pop back to normal. It kept doing this on and off every 20 seconds or so. I switched it off, fiddled with the antenna and all that, and eventually got it working fine by plugging it directly into the wall instead of using it on a power strip.
So, okay, maybe that's the problem?
Except then it started up again. Same issue, and it's gotten worse. When I unplug the converter box and antenna, I'm getting a sort of grainy, lit screen, but there's no "snow" if that makes sense. At this point, it's doing it all the time on power up.
Here's a video of what it looks and sounds like as of today:
https://www.youtube.com/watch?v=1joh...ature=youtu.be
I have a couple theories. First, I ordered a few new tubes for the tuner. I'm thinking I may have a dying RF amp tube, but that's just a wild guess. I suppose it could also be a weak mixer/oscillator. Whatever the problem is, it has to be before the audio and video are separated.
I'm also wondering if there isn't a wiring problem in the wall, since it got better before when I switched to a direct connection. I'm going to try moving to a different location and seeing if that improves things. If it does, I may be looking at a house problem and not a television problem.
If anyone has any theories on what this looks like, though, please let me know. I'm a bit stumped by the fact that, at least before today, it would be fine for awhile before suddenly doing this. Seems like a heating problem, which is why I'm saying tube, but I'm no expert.