Richard Harrison wrote:
J.D. Kraus wrote on page 185 of his 1950 edition of "Antennas":
"Thus, a helix with circumference too small for the axial mode of
radiation (circumferennce less than 2/3 wavelength) has a nearly
sinusoidal current distribution, caused by alternate reinforcement and
cancellation of two oppositely directed traveling waves on the helix of
nearly equal amplitude Izero as suggested in Fig. 7-13c. Both traveling
waves are of the Tzero transmission mode type."

Over on qrz.com, Tom was trying to prove Kraus wrong when he said in
"Antennas for All Applications", 3rd edition: "A coil (or trap) can
also act as a 180 degree phase shifter as in the collinear array
of 4 in-phase 1/2WL elements in Fig. 23-21B. Here the elements
present a high impedance to the coil which may be resonated without
an external capacitor due to its distributed capacitance. The coil
may also be thought of as a coiled-up 1/2WL element."

In trying to prove one could not obtain Kraus' 180 degree phase shift
with a coil [because everyone knows the phase shift is always zero],
Tom accidentally let slip the following - quoted from qrz.com:

W8JI wrote:
"By the way, I swept S12 phase with my network analyzer on a
100uH inductor a few hours ago while working on a phasing
system. The phase shift through that series inductor was about
-60 or -70 degrees on 1 MHz, ... "

Say what? Tom reporting a phase shift through an inductor? Will
miracles never cease?
--
73, Cecil http://www.qsl.net/w5dxp