Quote:
Originally Posted by timmy
i know mica caps in the hv area are sometimes used for oscillator timing, are these known to go bad even as old is 1949, some say they dont go bad but i dont know.
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In the past I have read about confusion over the mica or micamold caps found in older equipment. What I read is that there were two kinds that were almost physically identical. One type was actually a true mica capacitor which is known to be very reliable and almost never need replacing. The second type was evidently a wax/paper cap wrapped up in the same type casing as the mica with the horrible color dot identifiers.
Of course the wax/paper would be the ones to replace. It all boils down to simply getting rid of all wax/paper caps as well as electrolytic on a VERY old set an starting from there with any further repair if any is even needed. Also, if I were to do this semi restoration on a very old set (as I have), I would let the set work for several hours over a period of days. I have found that the longer a set works, the more "kinks" just go away more or less.
Finally, the selenium rectifiers will let you know when they fail as a smell like no other will fill your air space.
