>Mu is about 35 what is "a triode
>needs a Mu of c. 3 max."?
** In order for a triode to be linear in grid-driven configuration,
grid-cuurent can not be allowed to flow. In other words, the grid can
not be driven positive. Maximal cathode current flows at 0 grid-V.
Since the only triodes that draw maximal current at 0 grid-V have a Mu of
2-3, a tube with a higher Mu won't do. Since considerable grid-V is
needed to drive a low Mu triode, grid-driven triode linear amplifiers are
impractical at HF due to grid-C.
> I am missing some a key word here I think.
>I have run a pair of 250th's in parallel GG driven by a pair of 6146B in my
>younger years.
>1KW plate input power was the limit then so that was my goal. They have a
>mu of 37.
** Any triode will work in g-g linear service. The higher the Mu, the
higher the v-gain.
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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