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Sorta newbie 38-690 low volume
#31

Well I think we've confirmed that the bass section is not functioning correctly.  I pulled the 6K7 bass amp tube and there was no change in output.  I de-soldered the high path circuit and although there was some sound, it was very very weak, distorted, and almost inaudible.  I re-soldered it and back to square one.  I poked around a lot about the 6K7 and didn't find anything.  My only question is the ground on the audio cable.  Is that a grounded shield?  Should cap 136 go to ground? Mine does not.

On a positive note, I'm picking up stations on the 690 from EVERYWHERE!  Once the sun goes down it's non stop from one end of the dial to the other.  Unbelievably sensitive!

Even though my 690 is still sick, I could not have gotten to this point of the diagnosis without your help. Thank you SOOOOO MUCH!!!

BTW I've got a line on an Airline model 62-418 movie dial at the local online auction.  So many radios, so little time! 

Thanks Mike!


Messages In This Thread
Sorta newbie 38-690 low volume - by Hot Rod - 11-29-2017, 09:35 PM
RE: Sorta newbie 38-690 low volume - by morzh - 11-30-2017, 12:22 AM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 11-30-2017, 01:46 PM
RE: Sorta newbie 38-690 low volume - by morzh - 11-30-2017, 02:08 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 11-30-2017, 07:45 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-01-2017, 12:15 AM
RE: Sorta newbie 38-690 low volume - by morzh - 12-01-2017, 12:13 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-01-2017, 01:08 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-01-2017, 04:36 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-03-2017, 05:50 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-03-2017, 07:20 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-03-2017, 07:37 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-03-2017, 11:24 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-05-2017, 09:33 AM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-05-2017, 07:44 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-05-2017, 07:46 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-05-2017, 09:28 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-06-2017, 12:03 AM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-06-2017, 01:45 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-06-2017, 02:26 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-07-2017, 08:37 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-07-2017, 08:46 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-07-2017, 09:47 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-07-2017, 11:57 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-08-2017, 01:19 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-08-2017, 02:39 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-09-2017, 12:21 AM
RE: Sorta newbie 38-690 low volume - by morzh - 12-09-2017, 11:26 AM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-09-2017, 02:39 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-09-2017, 04:01 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-09-2017, 08:04 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-09-2017, 09:37 PM
RE: Sorta newbie 38-690 low volume - by Hot Rod - 12-10-2017, 08:01 PM
RE: Sorta newbie 38-690 low volume - by morzh - 12-10-2017, 08:23 PM



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