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Cecil Moore[_2_] · March 28th 09, 05:10 PM posted to rec.radio.amateur.antenna

wrote:
... has anyone had experience
using a toroid wound with the correct amount of reactance installed
on the element to to achieve resonance instead of a coil and how it
has been for them.

I've only one data point based on measurements made
at a California 75m mobile shootout.

K7JEB had this one mounted on a full-sized pickup.
An 8.5 foot whip using a 75m Texas Bugcatcher coil
at the base outperformed my antenna by +7dB.

I had this one mounted on a full-sized pickup.
An 11.5 foot whip using an SG-230 autotuner at the
base.

Not exactly the comparison you are seeking but the
SG-230 did use #2 iron powder toroidal inductors.

One might assume that the 6 inch long air-core
bugcatcher coil contributed more radiation than the
toroidal inductors. Seems to me the large air-core
coil occupies a greater number of degrees of antenna
than does toroidal inductor. This could be proved
(or disproved) by making delay measurements on both
coils using traveling wave current.

Previous such measurements are worthless for such
because the total current used was primarily standing-
wave current and was changing phase by only ~1 deg
for every ~30 degrees of antenna wire or coil.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com