10-23-2022, 07:04 PM
OK, so...
I checked the pwr xfmr output, high voltage - good, 5V to the 80's filament - good.
Put all the tubes, checked for the short B+ to GND/Centertap - good.
Turned on, waited for the B+ to rise to 150V or so, then after a while brought it up all the way.
Heard the reception noise, tuned to the local station, got somewhat distorted reception.
Noticed the shadowmeter worked great.
Then tried the tone control, and heard whistling in all positions.
Looked at the 77 1st AF stage, the grid wire was outside the shield, thought that would be it, but no, same behaviour.
Then I touched the 77's grid and saw faint violet glow.
I replaced the 77, and the reception came undistorted, and the tone control worked fine. No glow either. The tube that glowed was checked for gas....oh well.
I am still thinking if I Ineed to fix the speaker cone and spider.
Also the toggle switch (interstation noise suppression) does not work, so I will have to either fix it or replace it.
I checked the pwr xfmr output, high voltage - good, 5V to the 80's filament - good.
Put all the tubes, checked for the short B+ to GND/Centertap - good.
Turned on, waited for the B+ to rise to 150V or so, then after a while brought it up all the way.
Heard the reception noise, tuned to the local station, got somewhat distorted reception.
Noticed the shadowmeter worked great.
Then tried the tone control, and heard whistling in all positions.
Looked at the 77 1st AF stage, the grid wire was outside the shield, thought that would be it, but no, same behaviour.
Then I touched the 77's grid and saw faint violet glow.
I replaced the 77, and the reception came undistorted, and the tone control worked fine. No glow either. The tube that glowed was checked for gas....oh well.
I am still thinking if I Ineed to fix the speaker cone and spider.
Also the toggle switch (interstation noise suppression) does not work, so I will have to either fix it or replace it.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.