> >>When you come up with a value from the above formula, you
> >>can then substitute a non-inductive resistor of the calculated
> >>value for the tube and use your noise bridge or MFJ analyser
> >>to park your tuned input in the middle of the band.
> >
> >I wouldn't substitute, but put in parallel.
>
> As long as the tube ain't lit or is in cuttoff, it makes no
> difference. I usually have this chore done before I take the tube
> out of the box!
>
Yes it does. There are capacitances which are formed by the physical
structure of the tube. Take out your capacitance meter and try it. They
will effect the adjustment of the input network. The effects might be
small, but they are there, especially at the higher bands.
Gerard, AA3ES
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