Phil, thanks for the following:
"A roller coil gives the advantage of being able to tune the tank
for maximum efficiency at any power setting and frees one from many
hours of tapping a fixed coil in place in a new amp.
It is very simple; you tune the tank circuit for maximum power output.
With a roller coil, you just have one more item to tune.
Antenna tuners with roller coils work the same way. A tapped coil
may not be close enough to give a perfect match in every case."
(((73)))
Phil, K5PC
BUT,
Couldn't (wouldn't) maximum output likely correspond to a rather low-Q
setting of L1, rather than the usual 10 or 12? With a high L to C ratio
in the pi-net, efficiency is improved at the expense of harmonic
attenuation (low, loaded tank Q).
So, it seems to me, just tuning all three components for maximum, full
bore output, could end a person up with an undesireable loaded Q tank
situation.
Other comments please. (My danged ISP dumped all my e-mail, so I had to
retrieve the responses from the archives after I realized what had
happened--and the ISP admitted to it--sorry for the delay).
73, Roy K6XK Iowa
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