66 zenith high voltage dies after 30 minutes

[kx250rider]

If the horizontal is still running fine, and the HV isn't being loaded down, I wonder if that 1.5K @1-watt resistor (R106?; can't quite read the middle digit) is going up in value as it heats up? It's the only thing I see that could do that; assuming that it's NOT a load-down problem and that the horizontal oscillator and output are running, and that you've swapped out the rectifier.

Charles

[ctc17]

Originally Posted by kx250rider

If the horizontal is still running fine, and the HV isn't being loaded down, I wonder if that 1.5K @1-watt resistor (R106?; can't quite read the middle digit) is going up in value as it heats up? It's the only thing I see that could do that; assuming that it's NOT a load-down problem and that the horizontal oscillator and output are running, and that you've swapped out the rectifier.

Charles

Yes it blooms out. I have a hv probe so I can watch it. The hv also goes away at the reg tube so I dont think its that resistor.

Im going to go dig in right now for a few hours. Ill get some more info posted soon. Thanks again for the ideas. Ill check them out.