07-06-2026, 08:21 PM
Tim;
Those miserable silver mica caps in those cans can detune things, but I've never determined whether it is because the capacity of them goes up, or down. Mostly what I run into is intermittent contact between the silver deposits and the outside world, which can detune the transformer. I've seen two viable methods for replacement, one is to measure the capacity of the old cap, the other is to remove the old cap, install a trimmer, and adjust accordingly, thereafter you can either leave the trimmer in place or measure it's capacity, and replace it with a silver mica or C0G/NP0 rated cap of the nearest value. To be truthful set with these problems tend to get put on the back of the pile, I have enough older radios without these junky IF cans in them to keep me busy for the next several years.
Regards
Arran
Those miserable silver mica caps in those cans can detune things, but I've never determined whether it is because the capacity of them goes up, or down. Mostly what I run into is intermittent contact between the silver deposits and the outside world, which can detune the transformer. I've seen two viable methods for replacement, one is to measure the capacity of the old cap, the other is to remove the old cap, install a trimmer, and adjust accordingly, thereafter you can either leave the trimmer in place or measure it's capacity, and replace it with a silver mica or C0G/NP0 rated cap of the nearest value. To be truthful set with these problems tend to get put on the back of the pile, I have enough older radios without these junky IF cans in them to keep me busy for the next several years.
Regards
Arran
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