Re: Redesigning/tuning a coil

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Original poster: pepperman-at-SoftHome-dot-net 

Thanks for the suggestions.  I'll stay away from the off-axis
inductor--I don't want to reduce the coupling.  I was thinking about
adding wire to the primary to get enough turns; however, we were
able to find a bit more of the copper tubing (about 8 feet, I think),
which brings the primary to around 10 turns.

A possible solution: I think I may attach some scrap wire to the end
of the 1/4" copper tubing primary when checking for resonance, to
extend the effective length of the primary out to 25-30 turns as Dr.
Resonance suggested, and then add capacitance until the coil
tunes in the copper tubing section of the primary.  Then I'll remove
the scrap wire.  I hope to get the coil all set up and tuned before I
have to leave, but it'll be very, very close!

Michael Johnson