> From: km1h@juno.com
> Directly grounding the grids in an otherwise unmodified 220 is asking for
> fireworks and possible tube destruction. I also suspect that those stock
> parasitic suppressors are junk by now.
Nonsense Carl.
The last thing you want, if the tube faults, is to have the grid fly
up to 3000 volts.
If the grid, because of series resistance, reaches anode voltage
levels during a fault... the next stop for the arc is the filament
and everything connected to the filament including the exciter.
A HV series resistance is the way to go. Sticking a surge resistor
in the grid path is unwise, to say the least. Anyone doubting that
should ask Eimac or Svetlana.
73, Tom W8JI
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