K9YC writes:
I disagree with this advice, Tim. Such a choke is strongly inductive below about 30 MHz,
so > its common mode Z will be cancelled, at least in part, by the capacitance of a
feedline > shorter than a quarter wave. A multiturn choke wound on one or more #31
cores is > predominantly resistive, so performance is far less affected by the
impedance of the common mode circuit.
Most of the comments on 4 squares have been qualitative, such as "my
4-square works fine with 1 twisted, semi-elevated, half-radial".
However, in K3LR's case, he has actual measurements of the performance
of his 4-squares, including F/B and F/S measurements. If there was a
problem with the W0IYH-style chokes, wouldn't it show up in his
measurements ? How much better would the performance be with a multiturn
choke ? Over real ground, in the presence of real, possibly interacting
structures within N wavelengths, isn't there a finite limit to the
performance, regardless of your choice of "excellent" vs. "superb"
common-mode chokes ?
73,
Steve, N2IC
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