> Yes, the capacity hat was connected to the top of the
coil with a wire.
> The extra delrin rod was merely to put some distance
between the coil and
> the capacity hat in order to reduce the capacitive
coupling between the two.
> I figured the delrin rod and wire was the least disruptive
of the coil Q,
I understand now.
I don't think it would have a large effect either way. The
capacitance of the hat should dominate the system compared
to any supporting rod. There is very little "shorted turn"
effect or capacitance except when a coil has a large metal
end cap. That's part of the reason a hat near the coil end
might not be good. The large area of the hat adds
capacitance directly from coil end-to-end.
Short antennas often have esoteric interactions that often
can be sorted out only with FS readings, but the general
rule is to keep a hat as far above a loading coil as
practical. If the hat is big enough to dominate distributed
capacitance of the system, the coil can be placed near the
bottom with very little change in current distribution.
73 Tom
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