Posts: 201
Threads: 26
Joined: Dec 2005
City: Morris Plains, NJ
Under strong pressure to complete a Philco 19, I easily swapped a dud 36 tetrode in a charred tube socket to a 6SJ7 and a new porcelain socket. The only wiring change was the grounding of the suppressor grid. I didn't have any spare 36's or 77's at the moment. At some time in the future the owner may want it converted back to a 36 tube but until then the radio works fine on both bands.
Pete AI2V
Posts: 4,682
Threads: 51
Joined: Sep 2008
City: Sandwick, BC, CA
I wonder how a socket for a type 36 would get charred? It isn't a rectifier, nor a power output tube, it's an RF amplifier tube, so unless it somehow got hit by lightning someone must have really molested the set.
Regards
Arran
Posts: 201
Threads: 26
Joined: Dec 2005
City: Morris Plains, NJ
It was a charred arcing path from the plate connection to ground; most likely it started with a liquid of some sort getting on the socket. Normally this is only found in audio output and rectifier stages but it's not confined to those.
Pete AI2V
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Sometimes you gotta do what ya gotta do...especially when you have an owner who wants the set fixed yesterday. Good job in getting another one going again.
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Ron Ramirez
Ferdinand IN
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
When I do a switcheroo, I always stick a note inside saying what I did and why. Just so the next old fart doesn't have to scratch his bald head.