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March 8th 06, 01:36 PM posted to rec.radio.amateur.antenna

wrote:
Then we can't go further with this Cecil, ...

That's simply not true. We can take this discussion to its
logical conclusion if you are not afraid to continue it in
logical order at a logical starting point.

Starting with coils is like looking for your keys under the
street light, instead of where you lost them, because that's
where the light is better.

Coil theory is not the problem. Standing wave current theory
is the problem. Let's discuss the problem.

If you refuse to discuss the behavior or electrical characteristics of
the component you are talking about, there really isn't anything we can
talk about.

I'm not refusing to discuss anything as long as it is taken
in logical order. Our disagreement extends much farther back
into fundamental technical principles than just the subject of
coil function. We actually may have no technical disagreement
about coils. I believe our basic disagreement involves standing
wave current, not coils, so standing wave current should be the
topic of this initial discussion. For that, we need to first
agree on the 1/2WL thin wire model of a dipole.

Let's see what we can agree on. Can we agree on the following
pertaining to a 1/2 wavelength thin wire dipole?

The net current in a standing wave antenna is a standing wave.
The net current displayed by EZNEC for a standing wave antenna
is a standing wave. The net standing wave current is the phasor
sum of the forward current traveling wave and the reflected
current traveling wave. The principle of superposition applies
to the two component waves. If we superpose the forward current
traveling wave and the reflected current traveling wave, we
obtain the net standing wave current.

Let's take for instance, that 1/2WL thin wire dipole. The standing
wave current distribution and phase appears in Figure 14-2 in
Kraus and Figures 1.15 and 4.8 in Balanis. If the current at the
feedpoint is 1 amp, the net standing wave current equals cosine(x)
where 'x' is the distance in degrees away from the feedpoint.

This topic of discussion will most likely reveal that our fundamental
point of disagreement is standing wave current and not coils at all.
So which points above do you agree/disagree with?

References to Kraus are from "Antennas for All Applications",
Kraus and Marhefka, 3rd edition.

References to Balanis are from "Antenna Theory", Balanis,
2nd edition.
--
73, Cecil http://www.qsl.net/w5dxp

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