? Semi-agreed. However, under full drive, the grid/cathode potential
is typically110v-peak, or 78V-rms. Grid dissipation is approx. 0.15a x
78v = 11.7w. The rated grid-dissipation is 20w.
What part do you agree with?
Does full drive mean 65W? I had the impression that the tube was being hit
with more drive than that (perhaps as much as the unfathomable 100W limit
stated in the manual.) That would make sense, because the tube would not
have loaded up normally at 65W if the plate choke was resonant on 17M,
tempting the operator to increase the drive further and twist the load knob
more. Wouldn't the excess drive increase the grid/cathode potential and
grid-dissipation, perhaps fatally?
It's interesting that the hole in the tube was facing the plate choke. Did
the choke's resonance on 17M have something to do with that?
73, Dick WC1M
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