>*Sigh!"* Ian was right after all, Peter - you awakened the monster and now
>he's on the rampage again.
>
>Rich, I think you have your Dick's mixed. The first short posting below was
>mine - a basic observation straight out of "standard AC circuit analysis"
>with no reference to "Q" and nothing to do with "Wes' measurements."
>
>It's harmless to talk about VHF "Q" all you want, but with respect to
>suppressing VHF parasitics, the only Q in the anode circuit that really
>counts is the loaded "Q" of the entire anode parasitic circuit, on whatever
>frequency it ends up resonant.
? amen. In other words, the Rp of the interconnecting leads plus the Rp
of the parasitic suppressor are determiners of vhf voltage amplification.
.
>In that practical context, it's the complex
>impedance of the parasitic suppressor that's directly relevant, not its "Q"
? Is not Q is derived from other two?.
>Even then, overall feedback loop gain determines whether or not oscillation
>will occur, so loaded Q of the parasitic-resonant circuit is only part of
>the equation.
? agreed. If VHF Rp is proportional to VHF voltage amplification, the
suppressor's VHF Rp is important. According to Wes' measurements at
100MHz, the Rp of the copper-wire suppressor was 64% higher than the Rp
of the resistance-wire suppressor. The Q of the copper wire suppressor
was 46% higher. Throughout Wes' measurements, one can see a fairly close
relationship between vhf Q and vhf Rp. In other words, build a
suppressor with a lower Q at the anode-resonance and you get a lower Rp
at the anode-resonance - which reduces stage gain at the anode-resonance.
.
>...........
- later, Dick.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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