Thread: Dish reflector
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Old April 30th 09, 11:26 PM posted to rec.radio.amateur.antenna
Jim Kelley Jim Kelley is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Dish reflector

Cecil Moore wrote:
Jim Kelley wrote:
So I guess that ups the total now to at least two that we know of.
Just exactly how many different kinds of alternating current do you
reckon there are, Cecil? :-)


The point is that the current in a pure standing wave has
a different equation from the current in a pure traveling
wave.


No, actually the point was the name.

Any fields and waves reference book will have those
equations.


And what they don't have is different and assorted pet names for current.

The current in a pure standing wave cannot be
used to measure any kind of phase shift between points
because the phase doesn't shift between points on a wire
or on a coil.


If there is no difference in the relative phase of the forward and
reflected waves, then there is no change in the amplitude of the
standing wave in x. But when there is a change in the amplitude of the
standing wave in x, and I max is known, then determining the shift in
phase from the equation is a no brainer, Cecil. Other than Imax (and
you claim that assuming it's unity is good enough), there's virtually
nothing else that determines the amplitude of the standing wave envelope
along x. Helloooo.

The current in a standing-wave antenna, like
a loaded mobile antenna, is primarily standing wave current.


And you keep saying that as if it had some special significance.

ac6xg