Agreed. Thanks for the clarification since I missed it was the plates
glowing and assumed it was the filaments. Sounds like he has a short
loading the output of the tubes in question.

Bob

"Sam Goldwasser" wrote in message
...
"Bob Shuman" writes:

The diodes were my thought as well, but this may not give the necessary
control since voltage drop must be a multiple of the bias voltage. But
this
will certainly get you closer and help determine if you have another
problem
that is causing the filaments to glow so red hot.

He said the plates are glowing red. That's not a filament voltage
problem.

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