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Old 01-31-2015, 01:44 PM
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init4fun init4fun is offline
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Quote:
Originally Posted by radionut View Post
Hi all, got an interesting issue with a newly recapped Philco 50t-1400.It's developed a vertical (intermittent)ripple when the volume is turned up.If you turn the volume down it disappears? strange.........any idea's? Thanks .I've changed tubes ,no effect......
Very well could be electrically coupled , or it could be the vibrating speaker rattling something on the chassis like a bad solder connection (mechanical coupling of the sound to the problem)

If you disconnect the set's speaker and turn the volume way up , and the problem is still there , I'd guess electrically coupled . If the problem doesn't happen with the speaker disconnected and the volume way up then I'd be looking for a poor solder joint in the Vertical circuit or other microphonics as Jr Tech suggested . If it does turn out to be electrically coupled a somewhat gassy audio output tube could be throwing some strange stuff on the B+ line , I know you said you tried substituting tubes , does that include the audio tube(s) as well ?

PS , does lightly tapping on the set produce the picture distortion ?
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