38-690 audio problem

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38-690 audio problem

chucka
Junior Member

Posts: 19
Threads: 2
Joined: Jul 2012
City: Perkasie, PA

08-06-2012, 12:44 AM

Ron,

Yes I had seen the service note and made those mods.

Resistance readings on the transformer:

Winding_________Measured___________Schematic

Primary__________850 ohms___________475 ohms
6L6 Grid #1______270 ohms____________260 ohms
6L6 Grid #2______287 ohms____________260 ohms
Tweeter___________8 ohms______________???

Primary seems way high unless the schematic is wrong, tweeter winding, don't know, can anyone take reading on a known good set and check against my reading?

I did manage to redraw and simplify the complete audio circuit from 1st AF to speakers and believe I have a good idea on how the system works.
I was curious if there was a theory of operation paper somewhere.

Chuck

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Messages In This Thread

38-690 audio problem - by chucka - 08-05-2012, 12:57 PM

RE: 38-690 audio problem - by morzh - 08-05-2012, 02:22 PM

RE: 38-690 audio problem - by Ron Ramirez - 08-05-2012, 04:15 PM

RE: 38-690 audio problem - by chucka - 08-06-2012, 12:44 AM

RE: 38-690 audio problem - by codefox1 - 08-06-2012, 11:02 AM

RE: 38-690 audio problem - by Ron Ramirez - 08-06-2012, 03:51 PM

RE: 38-690 audio problem - by Ron Ramirez - 08-08-2012, 08:08 PM

RE: 38-690 audio problem - by chucka - 08-25-2012, 05:25 PM

RE: 38-690 audio problem - by chucka - 09-08-2012, 09:45 AM

RE: 38-690 audio problem - by jerryhawthorne - 09-08-2012, 11:09 PM

RE: 38-690 audio problem - by Ron Ramirez - 09-09-2012, 09:46 AM

RE: 38-690 audio problem - by jerryhawthorne - 09-09-2012, 01:34 PM

RE: 38-690 audio problem - by chucka - 09-10-2012, 10:17 PM

RE: 38-690 audio problem - by jerryhawthorne - 09-13-2012, 10:57 PM

RE: 38-690 audio problem - by chucka - 09-13-2012, 11:25 PM

RE: 38-690 audio problem - by jerryhawthorne - 09-13-2012, 11:41 PM

RE: 38-690 audio problem - by Ron Ramirez - 09-14-2012, 05:47 AM

RE: 38-690 audio problem - by chucka - 09-14-2012, 07:46 AM

RE: 38-690 audio problem - by chucka - 09-14-2012, 02:46 PM

RE: 38-690 audio problem - by Diverted - 03-17-2015, 11:32 AM

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