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Cecil Moore[_2_] · April 2nd 09, 11:17 PM posted to rec.radio.amateur.antenna

wrote:
My understanding is that
depending on on what the reactance is at some freq, I need to offset
this negative reactance with an equal positive reactance. I wasn't
looking at from a degrees point for view.

It depends upon which math model is being used and
whether the math model is valid under the existing
conditions. We can neutralize capacitive reactance
with a lumped inductance or with a stub or with a
helical coil. The results are approximately the
same but there are differences.

If the current amplitude changes significantly
between the bottom and top of the loading coil,
the lumped circuit model is not valid because
the coil is an appreciable percentage of a
wavelength more akin to a transmission line
than a lumped circuit.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com