08-12-2014, 09:35 PM
Well,
After I soldered everything in place, fixed the speaker (changed the transformer, rigged the new wires) etc, I checked the 5V AC at 80's filament while bringing it on Variac, and then put in the tubes.
The high voltage is OK.
Then I tried the volume....and almost fell off my chair for the radio gave out the loudest squeal! My daughter downstairs got scared, she thought it was one of her toys misbehaving.
The squeal is one tone, and it changes if I switch the tone control to the lower tone.
Which tells me it is an oscillation.
However I do not have shields installed, so who knows. Though why acoustic frequency....
Anyways, good news, speaker and sound obviously function, and the power section is OK.
Oh...and band switch is fully frozen. And it looks clean.
Any ideas as to how best unfreeze it?
After I soldered everything in place, fixed the speaker (changed the transformer, rigged the new wires) etc, I checked the 5V AC at 80's filament while bringing it on Variac, and then put in the tubes.
The high voltage is OK.
Then I tried the volume....and almost fell off my chair for the radio gave out the loudest squeal! My daughter downstairs got scared, she thought it was one of her toys misbehaving.
The squeal is one tone, and it changes if I switch the tone control to the lower tone.
Which tells me it is an oscillation.
However I do not have shields installed, so who knows. Though why acoustic frequency....
Anyways, good news, speaker and sound obviously function, and the power section is OK.
Oh...and band switch is fully frozen. And it looks clean.
Any ideas as to how best unfreeze it?