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Old March 16th 06, 10:51 PM posted to rec.radio.amateur.antenna
Gene Fuller
 
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Default Current through coils

Cecil,

You're a sly one, but not quite sly enough. 8-) 8-)

What is the meaning of "delay" in a standing wave antenna? Delay, like
phase, depends on the environment.

The measurement results reported by W8JI a few days ago stand on their
own. He described the setup and measurements adequately.

If you choose to make extrapolations to another environment, have at it.
Just don't expect anyone else to automatically agree with your
extrapolations.

As I recall, this three-year saga started with consideration of a loaded
mobile antenna, which I believe would be considered a standing wave
antenna. Have you since equipped your steed with a Beverage or rhombic?
Are phase shifts and delays now important?

73,
Gene
W4SZ


Cecil Moore wrote:
"Gene Fuller" wrote:..

Your messages seem to imply that there is some sort of characteristic
"phase shift" in a loading coil. Ain't so.



Thanks, Gene. What was implied is what has been reported as fact
by others - that the zero phase shift on both ends of a loading coil
measures the delay through the coil to be close to zero.


In the example of a standing wave antenna the phase shift is zero, both
experimentally and theoretically. (Approximate. Real world conditions
might cause small non-zero shifts.)



Please note that the phase shift in the wire is also zero. That the phase
shift is measured to be zero in a coil or a wire in a standing wave
environment is not of any practical importance whatsoever.


If you place this same loading coil in a traveling wave antenna you can
undoubtedly measure some sort of phase shift. (Exact amount left as an
exercise for the student.)



That was the discussion involving Dr. Corum's papers and the VF of
large RF inductors, like a 75m bugcatcher coil.
--
73, Cecil, W5DXP