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Next 38-690 question

Ron Ramirez
Silent Key

Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand State, Province, Country: Indiana

#15

01-01-2016, 12:10 AM

I'm thinking you may have a burned carbon track in your band switch, in the oscillator section. Which of course is not good news. Icon_sad

Either that, or something is shorting B+ to ground to drop your B+ voltage that much when the band switch is in one of the SW positions.

Some careful resistance measurements (with the set of and unplugged) might reveal the source of the trouble. I would measure resistance between the B+ line (both sides of resistor (44) and from there up to the oscillator "plate" or grid #2 of the 6A8G oscillator tube) and chassis ground with the set in all four of the SW positions. Also take these measurements in the AM position as a reference.

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Ron Ramirez
Ferdinand IN

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38-690 wiring question - by DKinYORKpa - 12-20-2015, 03:39 PM

RE: Next 38-690 question - by klondike98 - 12-28-2015, 11:07 PM

RE: Next 38-690 question - by Ron Ramirez - 12-29-2015, 06:52 AM

RE: Next 38-690 question - by DKinYORKpa - 12-29-2015, 11:52 AM

RE: Next 38-690 question - by Radioroslyn - 12-31-2015, 09:02 PM

RE: Next 38-690 question - by Ron Ramirez - 01-01-2016, 12:10 AM

RE: Next 38-690 question - by DKinYORKpa - 01-01-2016, 10:25 AM

RE: 38-690 wiring question - by Phlogiston - 12-20-2015, 04:18 PM

RE: 38-690 wiring question - by DKinYORKpa - 12-20-2015, 04:36 PM

RE: 38-690 wiring question - by DKinYORKpa - 12-20-2015, 04:44 PM

RE: 38-690 wiring question - by SteveJB - 12-22-2015, 11:02 PM

Next 38-690 question - by DKinYORKpa - 12-24-2015, 01:11 PM

RE: Next 38-690 question - by morzh - 12-24-2015, 07:09 PM

RE: Next 38-690 question - by Radioroslyn - 12-24-2015, 08:00 PM

RE: Next 38-690 question - by DKinYORKpa - 12-27-2015, 06:23 PM

38-690 SW bands - by DKinYORKpa - 12-28-2015, 07:23 PM

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