>...At -6000v, the anode-grid leakage
>was 0uA. At +4000v anode-grid leakage was 10uA - rapidly increasing at
>higher potentials.
>
>It is my opinion that 8877 s/n HSZ 501 probably died from gold boiling
>off of the grid.
Can someone educate me (and others)? I know very little about power grid
tubes, although I do know some physics.
What's the physical explanation of this rectification effect -- that
current flows when the grid is negative w.r.to the plate, but not when it's
positive? Is it just that, without gold on its surface, the metal of the
grid wire is a (better) field-emitter? But with the surface gilded, field
emission is negligible at the few-kV test potential? Whereas, the plate is
never a good field-emitter because E-field lines aren't concentrated on a
tiny point or line of it?
-Chuck W1HIS
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