OK the reflector is working now. Before, my message disappeared.

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I have a GU-78B that has developed a grid short. I have determined the grid short initiates about 2 minutes after power on and ends after about 5 minutes.

I have tried unsuccessfully to 'burn' the short by hooking up a 560?f capacitor fed with 300vdc.

What other methods that can be tried to 'burn' this short?

Doug

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