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37-650 fading performance
Tgace459
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Posts: 130
Threads: 25
Joined: Apr 2016
City: Buffalo NY
#1

09-15-2017, 01:38 PM
The 37-650 I have starts up fine and strong but fairly soon (5 min or less) starts to "fade out" to low volume. I have to turn the volume pot to almost max to get "normal volume".

If I touch or even get close to the grid cap of the 6K7 tube that attaches to the tuning cap I get full volume to return. I've swapped out the 6K7 tube but get the same results.

Any suggestions on where to start looking? Output tubes getting gassy as they heat up?
(This post was last modified: 09-15-2017, 01:43 PM by Tgace459.)
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Messages In This Thread
37-650 fading performance - by Tgace459 - 09-15-2017, 01:38 PM
RE: 37-650 fading performance - by Mondial - 09-15-2017, 09:58 PM
RE: 37-650 fading performance - by morzh - 09-18-2017, 10:11 PM
RE: 37-650 fading performance - by Tgace459 - 09-19-2017, 09:08 AM
RE: 37-650 fading performance - by morzh - 09-19-2017, 03:33 PM
RE: 37-650 fading performance - by Tgace459 - 10-24-2017, 04:20 PM



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