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Old October 30th 03, 04:17 AM
Cecil Moore
 
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Yuri Blanarovich wrote:
Any experiences out there, rather than more "reasons" why it ain't so?
Proper accommodation in modeling programs can give substantial improvement in
loaded elements modeling.


Assume a transmission line with an SWR of 10:1. Put a series inductor
in series with the transmission line. Assuming negligible losses, the
forward current is the same at each end of the coil and the reflected
current is the same at each end of the coil. The question is: Do the
superposed currents, Ifwd+Iref, remain constant? Of course not, because
of phase shifts. With a large enough coil, one could cause a current
maximum point on one side of the coil and a current minimum point on
the other side.

That same principle holds true for standing wave antennas which are
antennas with (surprise!) standing waves. The current is NOT the same
at each end of the coil (unless a current maximum or current minimum
occurs in the middle of the coil). However, for traveling wave antennas,
the current at each end of a loading coil would be close to equal.
--
73, Cecil http://www.qsl.net/w5dxp



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