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Philco 620B alignment woes
#15

I don't have first hand experience with the 75 tube problem. But, I have read elsewhere that it was in fact common to have a bad solder joint on the 75 tube grid connection causing intermittant or fluctuating audio levels. Your father may be right! I would re-solder that grid cap.

I think Brian mentioned this earlier, but check to make sure that you have the local oscillator running on the high side of the received signal (high side injection). On many radios it is possible to mis-adjust the oscillator to the low side of the signal (low side injection). Low side injection will cause the problems you are having with alignment.

Regards,

Ed


Messages In This Thread
Philco 620B alignment woes - by wonderwrench - 06-19-2008, 06:29 PM
[No subject] - by wonderwrench - 06-20-2008, 07:02 PM
[No subject] - by BDM - 06-20-2008, 07:19 PM
[No subject] - by wonderwrench - 06-20-2008, 07:46 PM
[No subject] - by BDM - 06-20-2008, 07:58 PM
[No subject] - by wonderwrench - 06-20-2008, 08:03 PM
[No subject] - by wonderwrench - 06-21-2008, 11:52 AM
[No subject] - by BDM - 06-21-2008, 12:24 PM
[No subject] - by wonderwrench - 06-21-2008, 12:51 PM
[No subject] - by BDM - 06-21-2008, 01:16 PM
[No subject] - by rghines1 - 06-21-2008, 01:33 PM
[No subject] - by BDM - 06-21-2008, 11:56 PM
[No subject] - by wonderwrench - 06-23-2008, 03:26 PM
[No subject] - by wonderwrench - 06-23-2008, 04:03 PM
[No subject] - by etech - 06-23-2008, 06:33 PM
[No subject] - by wonderwrench - 06-29-2008, 06:23 PM
[No subject] - by wonderwrench - 07-06-2008, 12:26 PM
[No subject] - by Ron Ramirez - 07-06-2008, 02:46 PM



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