> I think you'll find that if you do all the math that, for a typical
> loaded Q of 10-12 in the Pi-net, the coupling cap value should be 4X
> the value of the plate capacitor at the lowest frequency of operation.
Well let's see...
If the anode operating impedance is 3000 ohms and we use the
somewhat incorrect but common method of Rp/Xc = Q, then we
would have 300 ohms Xc with a Q of ten. That means the blocking
cap would be 75 ohms, which is without any doubt needlessly
large since it is in series with a 3000 ohm source impedance!
A blocking cap of even 500 ohms reactance would have a minimal
affect on anode impedance seen by the tank, so why make it so
large?
73, Tom W8JI
W8JI@contesting.com
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