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Hate to keep bugging our experts at the phorum, but I know you guys like the challenges.
I have this 10s464 that I just re-capped and have played for an afternoon, that after listening to for a few hours, noticed the volume would go Up and down occasionally.
I have had similar issues with other old radios.
Anyone care to comment?
Murf
(This post was last modified: 02-25-2018, 12:07 PM by
murf.)
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Could be dirty volume control pots or dirty tube pins/sockets.
John KK4ZLF
Lexington, KY
"illegitimis non carborundum"
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I did look into cleaning the pot, but this one does not an access hole for cleaning.
Probably could remove it and take it apart, but I am hoping that I won't have to take it out again.
Do generally clean the tube pins when I test the tubes.
Possibly a dirty socket?
Thanks,
murf
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More than likely the volume pot needs attention. AVC circuit (if equipped) could cause problems too, I would think, if not properly aligned.
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If it’s the volume control, I’d expect you to find dead spots as you rotate it through its range. If you find a spot where the radio plays and gets low, move the volume control a tiny bit up and down and that should pinpoint it.
Other things to look at are tubes and grid caps. Your radio has a loctal 1232 RF amp and the sockets are prone to intermittents. A wiggle of this tube when the volume drops will prove it.
Another thing you can do is inject audio into the TV input and switch to the TV setting. This will break the radio between RF and AF sections to help narrow it down. The tuning eye will also tell you if it’s in the front end. If the eye opens when the problem happens, it’s a RF issue.
Also there is a candohm (R18) resistor that is known to be the king of static and intermittents.
http://www.nostalgiaair.org/pagesbymodel...024689.pdf
Hope this helps.
Tony
“People may not remember how fast you did a job, but they will remember how well you did it”
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Thanks Tony,
Will check it out this week.
Have a great week!
Murf
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You too Murf. Hopefully the weather will cooperate. Let us know how you make out when time permits.
Tony
“People may not remember how fast you did a job, but they will remember how well you did it”