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I spent some time tonight digging through some old trade magazines. An invaluable resource. I have one box of articles, cut and pasted then organized in folders, all done by some very enterprising repairman way back when. One good article I found is from March/April '72, a Carl Babcoke review of color horizontal circuits. For whatever reason he chose to base it on a CTC7AA. The basics are very close, close enough for me to learn a lot. I don't know how much this will help me...one suggestion is to short the waveform coil while locking the horiz hold. Simple so I'll have to try it and see what happens. Meanwhile, our friend Frenchy had posted over on ARF regarding a possible contrast circuit mod. The -5 uses a different arrangement from later sets, variable bias instead of variable degeneration. I only know the technical jargon because I found an article from '65 that outlines how to rewire it to the newer circuit. Not sure if I want to do that; I'll work on fixing this problem first. From the brief description in the article this just might have some relation to my problem.
Another question: what type of caps should I use for replacing those low value micas? Looking at what I did in the past on that board, with some I was able to use an orange drop, on one I used a ceramic disc. I'm a little leary of that disc-my reasoning is that RCA could have used one back in '56 and they didn't, and there must have been a reason. I checked out the Mouser catalog and I see some muRata radial hv caps that look like they would work. One concern is that a couple of the old ones were rated at 1kv, something the muRatas can handle.
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Bryan
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