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Old March 17th 06, 04:40 PM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Current through coils


"Gene Fuller" wrote:
I never in my wildest dreams said anything about Tom's measurements.


Of course not and I certainly didn't mean to imply otherwise. What
you said was *objective and impersonal*, applicapable to anyone's
measurements and also applies directly to Tom's earlier measurements.

I don't believe that Tom set up a simple standing wave antenna and then
tried to measure the phase of the standing wave.


Maybe we should ask him. As I understand it, both Tom and Roy
set up a simple loaded 1/4WL resonant *standing wave* monopole
and measured the standing wave current at the bottom and top
of the coil. EZNEC could have told them that they wouldn't
measure any phase shift around the coil or anywhere else
around along the antenna..

It's an easy mistake to make to look at the current displayed
by EZNEC and picture that current flowing from the feedpoint
to the tip while being 100% radiated in the process so the
current falls to zero at the tip of the antenna. As we know,
those are not the technical facts. The reflected wave is a large
percentage of the forward wave.

As seen from the graphic at: http://www.qsl.net/w5dxp/3freq.gif

that standing wave current can have virtually any magnitude but
has a phase that comes only in near-zero or near-180 degrees
increments.

I've been asking how to obtain phase information from a
standing wave current. Nobody has answered.
--
73, Cecil, W5DXP