> Correct me if I am wrong, but doesn't the literature lists one more
> reason for having an LC based matching network in you amp? It tends
> to act as an energy storage medium for when the tube is in cutoff -
> the old flywheel analogy. A transformer wouldn't do the same thing.
> Or do I have it wrong in that this "flywheel" analogy only applies to
> the tank circuit on the output of the PA...........
I just assume everyone understands a bandpass or low pass circuit
with a reasonable working resonant Q also can not abruptly
change voltage.
But I believe the low-pass low-cathode-impedance description is
much more accurate. If we use highpass networks harmonics CAN
blow right through the network, so we'd have no "flywheel" for the
non-linear cathode impedance at harmonics! The exciter would see
the abrupt load changes in the form of harmonic energy.
If the network presents a high impedance at the cathode at
harmonics of the drive frequency, we'd have NO "flywheel" at the
cathode! It could float around with harmonics.
Because of that, I think the "flywheel" description is not correct
unless you qualify what frequencies it is a flywheel on, and how it
appears to the cathode.
73, Tom W8JI
W8JI@contesting.com
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