Lane,
For a high-Q circuit try about 31 turns #28 enamel
on TWO, STACKED, FT50-61 Amidon cores. (You may use
larger wire.) Use a small
"C". The Q will be about 290, as measured with a
HP Q meter. Like you said, there are other combinations
of L and C. In my case, the goal was a "high" inductance
with high Q and a small C, so that I could cover
the entire 160m band using a tuning diode.
As a comparison, the best one could hope for with
say, a plug-in coil of about 1.25" dia, would be a
Q of about 100.
Expect the high Q circuit to tune rather "sharply",
even more so with the cores in a tunable band-pass
filter. See "Solid State Design for the Radio
Amateur" published by the ARRL for more info.
One caveat, the higher the selectivity the more
loss in the network. One may want to use a
bandpass filter with low insertion loss prior
to the amplifier, followed by a narrow, tuneable
bandpass filter on the amplifier output IF the
goal is to sharply reduce strong out-of-band
signals and even some in-band signals
as well.
Good luck with your project!
73,
Charlie, N0TT
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