>Arlen says:
>
>>Yes, in a parallel circuit, Q is maximum when R=0. Here are the
>>equations:
>
>>In a parallel circuit, Q = X/R. X, of course, is frequency dependent,
>>and if R is made of a highly conductive material (nichrome, copper,
>>silver, etc) then R is also frequency-dependent, predictable by the skin
>>effect equations. But the frequency dependence of X will dominate.
>
>>In a series circuit Q = R/X
>
>NO NO NO NO!!!!!!!!!!!!!!!!!!!!!!
>
>In a series circuit, Q = X/R, while in parallel, Q = R/X. If you shunt an
>inductor witha low resistance, you kill the Q. If you wind an inductor with
>resistance wire (i.e. high series resistance), you kill the Q.
>
>So in the parallel case, as f goes down, X goes down, and for a given R, Q
>goes up.
>
>As various people have said, it's the damping of the whole circuit from
>plate through suppressor, DC blocker and tuning C that's important in
>suppressing the parasitic.
>
Amen, Peter
cheers
Rich...
R. L. Measures, 805-386-3734, AG6K
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