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Old 06-20-2024, 12:21 PM
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bandersen bandersen is offline
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I'm wrapping one up right now and all five of the 270pF mica IF coupling caps were bad. Symptom was poor gain. That might account for your tuner being weak.

Never had trouble with the white Hi-Q caps but of course anything is possible.

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Old 06-20-2024, 01:49 PM
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Yamamaya42 Yamamaya42 is offline
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Quote:
Originally Posted by bandersen View Post
I'm wrapping one up right now and all five of the 270pF mica IF coupling caps were bad. Symptom was poor gain. That might account for your tuner being weak.

Never had trouble with the white Hi-Q caps but of course anything is possible.

I just know that a third to a half of the ones in mine had rather soft like red ends, and a weird brown sap like stuff that seemed to be coming from them, I really did not get where it came from or how it got there, other that it must have come from the cap somehow.
I can post a pic of some before they were removed later.

And yes, the 270pF micas in mine are still OEM, and most likely need to be changed, but the tuner was in poor shape as well, but did work to some degree, looking inside, I could see insulation starting to come off of the wiring inside, I did try to clean contacts, but not too much, for fear of making it worse, the pair of 150 ohm resistors in the rf amp were quite out of tol when I tried to test them, how far , I don't recall.
This set, does not get snow with no input, but does get a picture (with some slight fuzz) with a normal rf modulator, and crystal clear when I BLAST it with a Blonder Tongue micm-d.
It can do with an alignment, as it's hard to get the sound and video to tune in at the same time, though I don't have sweep marker generator, I have the digital RF generator, which I used on the Arvin TV, which ironically is the only one of my older BW sets that gets snow with no input, meaning that they all could use a touch up.
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