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IF oscillation in Philco 38-12
cwc
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Posts: 6
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Joined: Nov 2015
City: Pine Island, MN
#9

12-28-2015, 11:01 PM
After some new caps, a new tube and an alignment my 38-12 seemed to be working fine so I put it in the living room  to see if it would run all day without a problem.

Well, it didn't.  After 2-3 hours the local oscillator changed frequency.  It didn't "drift", it was an abrupt shift down in frequency by about 35 Kc.  I repeated the test a few times and it repeated the shift consistently.

I assume this is a heat problem and know how to test the various components to track it down, but I thought I'd ask if this is a known problem with a known solution to save a bunch of tedious testing.  Icon_e_wink

Any suggestions will be appreciated.
Charlie
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Messages In This Thread
IF oscillation in Philco 38-12 - by cwc - 11-12-2015, 10:55 AM
RE: IF oscillation in Philco 38-12 - by cwc - 11-13-2015, 10:27 AM
RE: IF oscillation in Philco 38-12 - by David - 11-12-2015, 09:15 PM
RE: IF oscillation in Philco 38-12 - by cwc - 11-13-2015, 10:29 AM
RE: IF oscillation in Philco 38-12 - by cwc - 11-19-2015, 12:06 AM
RE: New problem in Philco 38-12 - by cwc - 12-28-2015, 11:01 PM
RE: IF oscillation in Philco 38-12 - by cwc - 12-29-2015, 11:49 AM



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