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48-206 - Tuning changes as it warms up
PAradiogeek
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Posts: 395
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#3

08-22-2015, 07:56 PM
Thanks for the suggestions Mondial

My 7A8 tested at 96/100 on my tester, but I realize that mixer tubes can be very finicky. Unfortunately, I don't have a spare in stock, so I will have to order one. In the meantime I'll try freezing that 47pf cap and replacing it if it is affected by the temp change.

Now that I think about it, those small value caps were usually mica weren't they? I wonder if a previous owner replaced the original cap with a cap that had a different temperature coefficient than the original. If so, that might be the cause of the problem. Sound reasonable?
(This post was last modified: 08-22-2015, 07:58 PM by PAradiogeek.)
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RE: 48-206 - Tuning changes as it warms up - by PAradiogeek - 08-22-2015, 07:56 PM



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