|
Well from what I can tell about the thermal cutout is that its first job limits the initial current rush. It takes the set longer to turn on, but protects the tubes filiments from that initial "flash" that most series strung sets have.
The second job is to act like a circuit breaker in the event of a short in the B+ it will open the thermal cutout.
I was just reading your first post and saw that one of the 12AT7's had an open heater. Same with my set. I had a spare Groove Tube 12AT7 that works just fine. The set had all origional GE 6AG5's that tested weak to marginal. If you read the service notes for the set, after 1950 replace ALL 6AG5's with the "new" 6BC5. AES had NOS 6BC5's for 1.50. I ordered 5 from them and one tested weak. I called and they were super nice and sent me out another 6BC5 no questions asked.
Best Regards,
Matt Davala
|