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Old January 7th 08, 04:01 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 2,951
Default Standing morphing to travelling waves. was r.r.a.a Laugh Riot!!!

On Mon, 07 Jan 2008 08:09:44 -0600, Cecil Moore
wrote:


http://www.w5dxp.com/rhombicT.EZ

This is a terminated rhombic in free space. The termination
resistor is 880 ohms and the 880 ohm feedpoint SWR is 1.032:1.


Which, of course, has nothing to do with Standing Waves ON THE
ANTENNA.

On wire 1, the variation that is swinging along the line like any
other Standing Wave antenna of length greater than a quarter wave. The
value is higher than your "source SWR," of course.

Take a look at the current with and without the phase.


Swinging 180 degrees at 6 or 7 degrees per segment. Exactly like my
earlier reports in contrast to your proclamations.

Then
compare that traveling-wave current to the standing-wave current
on a 1/2WL dipole. Or simply learn enough math to tell the
difference between Io*cos(kx)*cos(wt) and Io*cos(kx+wt).


I was there weeks ago ahead of you where the formula applies (on the
wire, not an EZNEC report of source SWR).

It was more interesting to compare your Rhombic to itself in a closer
to ground situation (elevated 12 feet above a real, high accuracy
ground).

SWR there, out of the gate (not at the source) and on the antenna wire
itself (where traveling waves would be presumed to inhabit the
design):
SWR: 1.15
Further down the wires, radiation loss does ameliorate this
SWR: 1.08
Still in excess of your Source SWR, which, obviously has nothing to do
with STANDING/TRAVELING WAVES ON THE WIRE.

Nice of you to confirm every point I made in refuting your claims.

Others are free to observe every classic indication of Standing Waves
upon a "Traveling Wave" antenna, complete with phase shift as I had
reported some time ago.