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Philco 38-690 restoration
#30

yes, the audio shorting construction is less than.....works in my radio but looks very unreliable.

As for the tweeters, there gotta be something wrong with the way you are measuring.
The tweeters are simply fed from an extra winding of the main interstage transformer with 1uF cap in series with the output (similar to 37-690 but there they use a separate transformer in parallel to the main one with the cap in the input winding). So there are no threshold elements etc, the output is always there, and the sound/signal cannot come and go abruptly. You have to use AC setting and make sure that your device can work as a true RMS at the frequency you are working at.

I use my Fluke DMM for it.


Messages In This Thread
Philco 38-690 restoration - by FStephenMasek - 04-18-2011, 09:30 PM
RE: Philco 38-690 restoration - by FStephenMasek - 04-13-2013, 12:47 PM
RE: Philco 38-690 restoration - by FStephenMasek - 04-13-2013, 09:16 PM
RE: Philco 38-690 restoration - by morzh - 04-13-2013, 09:22 PM
RE: Philco 38-690 restoration - by FStephenMasek - 02-17-2014, 12:35 PM
RE: Philco 38-690 restoration - by morzh - 02-17-2014, 12:43 PM
RE: Philco 38-690 restoration - by FStephenMasek - 02-17-2014, 10:13 PM
RE: Philco 38-690 restoration - by morzh - 02-17-2014, 10:16 PM
RE: Philco 38-690 restoration - by FStephenMasek - 06-22-2014, 12:04 AM
RE: Philco 38-690 restoration - by morzh - 06-22-2014, 10:56 AM
RE: Philco 38-690 restoration - by FStephenMasek - 06-22-2014, 01:01 PM
RE: Philco 38-690 restoration - by FStephenMasek - 06-22-2014, 07:18 PM
RE: Philco 38-690 restoration - by morzh - 06-22-2014, 08:44 PM
RE: Philco 38-690 restoration - by gregb - 06-22-2014, 08:47 PM
RE: Philco 38-690 restoration - by PhilcoJohn - 06-23-2014, 05:47 PM
RE: Philco 38-690 restoration - by morzh - 06-23-2014, 05:53 PM
RE: Philco 38-690 restoration - by FStephenMasek - 07-06-2014, 01:40 PM
RE: Philco 38-690 restoration - by morzh - 07-06-2014, 02:13 PM
RE: Philco 38-690 restoration - by FStephenMasek - 07-06-2014, 02:46 PM
RE: Philco 38-690 restoration - by morzh - 07-06-2014, 02:51 PM
RE: Philco 38-690 restoration - by FStephenMasek - 07-10-2014, 04:32 PM
RE: Philco 38-690 restoration - by morzh - 07-10-2014, 05:32 PM
RE: Philco 38-690 restoration - by FStephenMasek - 11-06-2014, 01:27 AM
RE: Philco 38-690 restoration - by sam - 11-06-2014, 03:57 AM
RE: Philco 38-690 restoration - by 462ron - 11-06-2014, 01:13 PM
RE: Philco 38-690 restoration - by klondike98 - 11-06-2014, 02:08 PM
RE: Philco 38-690 restoration - by morzh - 11-06-2014, 02:35 PM
RE: Philco 38-690 restoration - by FStephenMasek - 11-11-2014, 12:57 PM
RE: Philco 38-690 restoration - by morzh - 11-11-2014, 01:17 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-19-2011, 10:07 AM
Re: Philco 38-690 restoration - by FStephenMasek - 04-19-2011, 12:59 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-19-2011, 02:00 PM
Re: Philco 38-690 restoration - by FStephenMasek - 04-19-2011, 02:35 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-19-2011, 02:47 PM
Re: Philco 38-690 restoration - by FStephenMasek - 04-20-2011, 10:47 PM
Re: Philco 38-690 restoration - by Ron Ramirez - 04-21-2011, 07:41 AM
Re: Philco 38-690 restoration - by FStephenMasek - 04-26-2011, 10:06 PM



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