I assume that you're referring to the Boothe article. I've only found part 1 of
that, since ARRL in its infinite wisdom prevents download of the piece. But he
didn't need to measure this, it can be modeled; the EZNEC help file says: "The
currents at the ends of real loading coils are often substantially different
because of radiation and/or physical length. When this occurs, the EZNEC load
model, which has equal currents at the two terminals, does a poor job of
representing the coil, and considerable inaccuracy can result. Whenever
possible, a helix rather than a load should be used to model a loading coil."
I used a distributed coil model in a paper about short inductively loaded
antennas that I wrote 20 years ago and posted on the Rec.Radio.Amateur.Antenna
newsgroup.
Wes N7WS
On 7/4/2025 11:30 AM, Jim Brown wrote:
On 7/4/2025 8:39 AM, Wes wrote:
I "built" a model of a vertical in AutoEZ and used EZNEC Pro/2+ V 7.0 running
the NEC 5 engine to do the computations.
All good, but -- one of the things that long QEX piece showed is that EZNEC
doesn't correctly model inductive loading! They did this by comparing the
modeling result with measurements of built antennas.
73, Jim K9YC
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