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Old March 11th 06, 03:34 AM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Current through coils

John Popelish wrote:
the net charge movement is zero and therefore
the standing wave current is not "going" anywhere?


Sorry, no.


Gene just posted the equation for standing wave current.

Isw = 2Io cos (kz) cos (wt)

This is definitely not in the form of a traveling wave.
Hecht, in "Optics" says the standing wave does not move
through space. Presumably, for the same reason, a
standing wave does not move through a wire.

Looking
just at just current, and at only a single point, a traveling current
wave and a standing current wave are indistinguishable.


True but if you know the equation above, then they are distinguishable.

The only way to understand a standing wave having a phase of zero
degrees, that makes sense to me, is that it applies to all points
between one current node and the next.


Yes, the subject in context is 1/4WL monopoles or 1/2WL dipoles.

That's unclear to me. Why can't the E-field and H-field simply be
exchanging energy at a point rather than any net charge moving
laterally?


In an isolated EM plane wave, I think this is the case, and displacement
charge in space takes the place of conductor current. But when a wave is
guided by a conductor, we can measure the charge sloshing back and forth
in the conductor in response to those fields.


Yes, I was confused about that. If the question is changed to: "Why
can't the E-field and H-field simply be exchanging energy within each
1/4WL rather than any net charge moving out of that 1/4WL?", it would
make sense.

Thanks John, for the refresher course.
--
73, Cecil http://www.qsl.net/w5dxp