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Old March 17th 06, 12:39 AM posted to rec.radio.amateur.antenna
Cecil Moore
 
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Default Current through coils

Gene Fuller wrote:
What is the meaning of "delay" in a standing wave antenna?


Same as in a traveling wave antenna - the length of
time it takes a traveling wave signal to make it through
a coil or a wire. The lumped-circuit model assumes that
delay is equal to zero even for traveling wave antennas.

Delay, like phase, depends on the environment.


I defined what I meant by "delay" through a coil a few days
ago. It was the delay experienced by a traveling wave
flowing through a coil or 1/2 the delay experienced by
a traveling wave making a round trip to the end of a coil
and back based on the self-resonant frequency. That's what
the velocity factor calculations were all about. Does the
0.66 velocity factor disappear when RG-8 is used as a stub?
Then neither does the 0.0175 coil velocity factor disappear
when it is used in a standing wave environment.

The cos(kz)*cos(wt) nature of the standing wave current
prohibits that standing wave current from being used to
determine the velocity factor of a coil or of a wire. The
lumped-circuit model assumes the velocity factor through
any and every coil to be *greater than unity*.
--
73, Cecil http://www.qsl.net/w5dxp