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Power Transformer Temperature Question
#3

Terry,

Thanks for your tips. I'll take some measurements later in the week, if not tonight.

I have replaced all the tubular paper caps. I'm in the process of ordering replacements for the molded paper caps in the picofarad range. (Assuming I know how to tell the difference between the mica caps and molded paper ones--I'm not too sure.)

I replaced 6 or 7 resistors that were more than 10% out of spec. Two of the ones I replaced were the 1.0 Meg resistors in the bias circuit of the 41 tubes (#53 and #54.) One of those was reading 2.5 Megaohm and the other about 1.25. I think that would raise the grid bias voltage, wouldn't it?

I am also slowly replacing all of the rubber insulated wire. I've done the easy ones now, and am working on the nasty ones in the tight quarters near the band selector switch. I haven't tried to get into the interstage transformer cans yet.

Sometime in the past, someone replaced the 16 microfarad cap (#27A) with a 20 microfarad. I kept the 20 mf value when I replaced the old 'lytics because I read somewhere that going up a little in value was better.

John Honeycutt


Messages In This Thread
[No subject] - by Terry Burns - 06-19-2007, 12:34 PM
[No subject] - by Raleigh - 06-19-2007, 01:54 PM
[No subject] - by Raleigh - 06-19-2007, 09:52 PM
[No subject] - by Terry Burns - 06-20-2007, 08:31 AM



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