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So this TV had me confused. I was convinced I was hearing the sound of something arcing. The sound went away when I pulled the plate cap off the HO tube, and did not go away when I disconnected the HV rectifier. So I thought the problem had to be the fly or the yoke. But I put in a new fly and yoke (a merit mdf 120) and had the same results. I even tried changing the tube socket the yoke plugged into.
But it turns out that sound was a symptom of the horizontal oscillator not being at the right frequency and not what was causing it. I had two bad mica capacitors, once I changed them and the horizontal was going at the right frequency the sound I was hearing went away.
But if I adjust the horizontal to be down at the frequency it was at before, I still hear that noise. I doubt seriously the new fly and yoke are bad in any way. So if nothing is arcing, what is that awful sound I hear when the horizontal gets down around 14KHz coming from the yoke, or the flyback?
The horiz wouldn't lock when I first got those capacitors replaced, but that problem was the more commonly bad horiz afc diode. I've pretty much started replacing those automatically when I recap. Now I got a stash of those ECG 113s, and RCA SK 113s, but I have in the past just used two 1N4007 diodes, which seemed to work.
I'm going to have to remove the CRT to clean dirt off the front of it. But otherwise, this tv is done. That remote I have is in pretty bad condition, but it works, and I'm not going to do too much work repairing the case, because it's not the one that really belongs with this tv anyway. pics...
Last edited by Adam; 06-16-2014 at 09:15 PM.
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