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Re: Max anode voltage?

Original poster: Ed Phillips <evp@xxxxxxxxxxx>

I would like to believe I know what I am doing though I have not designed a
high power tube oscillator before.
I do not understand the fine detail on how the grid leak works or how to
handle the variable load presented by the tank and secondary under the
transient conditions of pulsed operation."

Your problem is not only one of designing a high power oscillator but designing of one feeding a resonant and variable load. Designing an oscillator for a resistive load isn't much different from designing a power amplifier for the same power level except that you have to figure out the feedback to get the required grid drive. Knowing the operating grid bias and grid current (part of the amplifier design) you can then choose the self-bias resistor (grid leak). The problem of course is getting the oscillator to start correctly so that the tube doesn't fry its little self due to lack of excitation with resultant grid drive.
When it comes to trying to drive a resonant load like a
TC, and particularly one where the load resistance and reactance both vary with output power and with time (streamer growth) things get a lot trickier. I know a fellow who was designed in designing a power oscillator for a cyclotron which UCLA built some time back and they had a devil of a time getting the thing to work because of the many possible modes of oscillation it had and of the difficulty of getting it to start in the correct one. I'm not sure they ever really succeeded. Somewhere I have a reprint of a paper they wrote but don't know where it is.