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In this TV, the Admiral 14R12 there are a total of 10 mica caps used. 1 is a high voltage (1500V) in the yoke which was not replaced, 3 in the RF/IF section, and the rest from the IF section on.
So out of 9 micas, there appears to be no problem replacing those 6 in the sweep circuits etc. That leaves 3 120pf micas (C17, C18, and C24) that seem to be subject of whether to change them or not. These cost me $2.39 each because I ordered 1% caps. A total of $7.17 for the 3. I do think the parts list listed at least 1 of them 3% hence why I got all three at 1% from Just Radios. I know overkill.
I replaced 9 electrolytics, 29 paper caps, 8 disc caps, and 9 micas. A total of 55 caps. To me changing 52 caps and then changing 3 more to have them all changed just makes better sense to me. Especially when we are warned not to even move the micas because it can cause the lead/case seal to fail and that will lead to problems down the road. This can happen when changing the resistors, etc. So I just change them to eliminate any problems, if any, by keeping 65 year old micas.
As several other posters have said, they do find micas in the RF/IF section failed.
I know there are those who really enjoy trouble shooting and good for you. I enjoy just as much a finished product that was made as good/better? as new when I'm finished and I don't have to wonder if an old component that I could have changed and didn't is going to fail latter on.
If I had a good source for the very low value ceramics, I'd probably look close into changing them as well.
Like I said " Everybody sees this hobby through their own set of eyes and gets out of it what they want to. Neither is right or wrong. But different approaches."
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