Quote:
Originally Posted by Tubejunke
Do you mean that the set as a whole runs cooler? Also, what do you think was keeping the B+ below specs and did bringing it up provide any noticable performance improvement?  |
Well at least one corner of it is cooler. That's where I've replaced the 20W filament dropper with a diode.
The old seleniums were keeping the voltage down. They got noticeably warm during operation. I suspect their resistance has increased over time.
As for performance - it's a mixed bag. I can get a brighter picture now, but the contrast isn't as good. Also the vertical retrace lines are more visible. The horizontal sync is still flaky like it has been since I first powered up the set. I suspect I need to replace the dual selenium AFC rectifier. The important thing is that i can stop worrying about the seleniums go up in smoke while I continue tweaking the set. I've had it happen once before and don't ever want to experience that again
I'm also checking the resistors more thoroughly than I did first time around. I'm considering replacing the germanium video detector diode while I have the set open too.