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48-482 no FM
#8

Yes, I believe the winding resistances are 21 and 1.5 ohms. Keep in mind that the FM windings of the IF transformers are always much lower in resistance than the AM windings. 15 ohms for the FM section would make no sense at all.

Have you tried to peak any of the FM portions of the IF transformers? The one you replaced will certainly need tuning. If you feed enough 9.1 MHz signal into the grid of the 7F8 (test point A), you should see some negative voltage on the AVC line, junction of R407 and R412. Try peaking each of the FM IF trimmer caps and see if you get a definite peak in output with each adjustment. If you don't see a peak with each coil, there is most likely a problem with that tuned circuit.


Messages In This Thread
48-482 no FM - by rebrands - 09-10-2017, 07:18 PM
RE: 48-482 no FM - by klondike98 - 09-10-2017, 07:57 PM
RE: 48-482 no FM - by Mondial - 09-10-2017, 08:41 PM
RE: 48-482 no FM - by rebrands - 09-10-2017, 09:50 PM
RE: 48-482 no FM - by rebrands - 09-12-2017, 01:35 PM
RE: 48-482 no FM - by robsradioactive - 09-14-2017, 07:23 PM
RE: 48-482 no FM - by rebrands - 09-14-2017, 10:19 PM
RE: 48-482 no FM - by Mondial - 09-15-2017, 12:35 AM
RE: 48-482 no FM - by rebrands - 09-15-2017, 04:28 PM
RE: 48-482 no FM - by Mondial - 09-15-2017, 09:22 PM
RE: 48-482 no FM - by rebrands - 09-15-2017, 10:44 PM
RE: 48-482 no FM - by rebrands - 09-16-2017, 11:06 PM
RE: 48-482 no FM - by robsradioactive - 09-17-2017, 06:38 PM
RE: 48-482 no FM - by rebrands - 09-19-2017, 12:37 AM
RE: 48-482 no FM - by klondike98 - 09-19-2017, 11:01 AM
RE: 48-482 no FM - by robsradioactive - 09-21-2017, 11:36 PM
RE: 48-482 no FM - by rebrands - 09-22-2017, 10:51 AM



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