66 zenith high voltage dies after 30 minutes

[ctc17]

Originally Posted by andy

Can you get a good RF arc from the HV rectifier plate cap?

Yes, ok just checked it out and it appears to be the HV rectifier. The boost voltage went up a bit and I got a good 1" arc off the cap of the rectifier when there was no hv on the cathode.

This time I got a good 30 seconds of color bars and funky colors before it died. Maybe the tube is arcing inside before it dies.

I cant see it glowing even when its working so I cant tell if the filament is going open. I let it run in my tube tester for an extended time and it didnt fail.

What a trip, I never would have expected a tube like this to fail after running for awhile. This is the one tube I dont have a replacement for, just got one coming off ebay.