The radio does not recover once it stops, and the audio goes completely away. I got it to come back once by removing and reinstalling the 41 tube, another by reinstalling one of the XXL's. I will continue substituting the tubes, and spray contact cleaner on the sockets. The radio was motorboating before I replaced most of the bypass caps, and gave the push button contact area a good spraying of cleaner. Somehow I loose voltage. I rechecked the soldering on my caps and they are all solid(at least appear to be).

Look for drifting, out of spec resistors in your downstream B+ supply. Did you change the filter caps?BTW, what radio is it?

Is this part of your other thread?

:Is this part of your other thread?
:
Yes, I do not know what happened with that. I do have a blow dryer,

::Is this part of your other thread?
::
:Yes, I do not know what happened with that. I do have a blow dryer,

You can maybe locate a thermal intermittent by warming up different areas of the chassis gently with a hair dryer, and using freeze to identify the exact component.
Lewis
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:The radio does not recover once it stops, and the audio goes completely away. I got it to come back once by removing and reinstalling the 41 tube, another by reinstalling one of the XXL's. I will continue substituting the tubes, and spray contact cleaner on the sockets. The radio was motorboating before I replaced most of the bypass caps, and gave the push button contact area a good spraying of cleaner. Somehow I loose voltage. I rechecked the soldering on my caps and they are all solid(at least appear to be).
: The XXL tube is an older version of the newer 7A7 tube. Why PHILCO did that maybe no one knows. The XXL & the 7A7 tubes are identical inside. I know because the one that Dad bought in 1941 has 2 XXL's in it & the radio shop guy told him it was a PHILCO "goof-up". The XXL is a VERY VERY hard tube to find. Only a person that has an old PHILCO ----Might---- have one. Otherwise it might be easier for the president to fire all of his staff than to find an XXL!