hi rich,
> If K is unity, the grid is tied to the cathode. Tying
> the grid to the cathode seems unlikely to produce
> amplification unless a (grounded) screen is present.
yup. the gain inherent in a tetrode is pretty effectively abolished,
and the tube functions as a low-mu triode!
> and cathode are at the same rf potential, and therefore
(note the term RF! ^^ right there!)
> there is no chance of the control grid drawing any
> current (assuming the tube is biased at a >reasonable
> operating point.) If the grid and cathode are at the
> same potential, the grid can not draw current even if
> the tube is biased at an UNreasonable operating point
YES, it can!! an UNreasonable operating point would be with the
control grid biased positively (DC) with respect to the cathode!
that would be not just an unreasonable operating point, but a *silly*
operating point, but the grid WOULD draw current, regardless of the
RF applied. that's exactly why i worded it that way.
i realize i started this
> >just picking nits....
but i am now withdrawing from the semantics-fest!
73,
George T. Daughters, K6GT
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