I'm beginning to think color sets are more trouble than they're worth.

[miniman82]

Did you clean out/replace the vertical height pot? They are prone to tin whiskers and being noisy due to age, but it could also be the vert position pot. Should be an easy fix.

[Phil Nelson]

Originally Posted by miniman82

vertical height pot? They are prone to tin whiskers

Funny you should mention that. This week I was working on a 1930s Stewart Warner radio that had a serious case of dendrites inside a potentiometer:



"Dendrites" are the fuzzy, bristly stuff growing down from above, in that view. (At least in NASA terminology. They use the term "whisker" for a slightly different phenomenon, the growth of a long, single metal hair rather than a bunch of fuzz.)

First time around, I opened up the pot case and gave it the usual DeOxit treatment without looking very closely. When problems persisted, I reopened it and discovered all that cute metal fuzz making intermittent shorts inside.

Dendrites clean off easily, but you can't count on simple spraying to get rid of them. They (or whiskers) can also form on the outside of a control, making a short from the control case or terminals to chassis or some other components.

Yet another reason to clean, clean, clean these old chassis, especially if they have been in a moist environment.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

[kvflyer]

BINGO!!! That was the problem with my Admiral 26R12. The height collapsed and the control did not "control" the voltage. A good cleaning of the pot fixed it. It was my first experience with tin whiskers...

Please, Don't give up...