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Old July 11th 07, 11:16 PM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
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Default Need help... End-fed, long wire or ????

Bruce in Alaska wrote in
:
Bruce,

An interesting post overall, but ...

System. All these tuners NEED a Low Impedance RF Ground to work
against, as well as a Longwire who's length is SPECIFICALLY set up to
put the 1/2 Wavelength Point in a non used portion of the Spectrum.
They will NOT tune within 2% of the Natural 1/2 Wavelenth point of the
Longwire connected, where Antenna Impedances near Infinity.


The "rules" above are offered without definition or explanation, so they
don't really raise the art.

Manufacturer's "rules" and explanations are often inconsistent. For
example, some state a minimum length that can be tuned on say 3.6MHz, and
it is often around 3m, yet they rabbit on about avoiding half wave
resonances in the wire to avoid high voltage at the feed point. The feed
point voltage on a 3m whip at 3.6MHz is likely to be much higher than a 10m
whip at its first parallel resonance.

Owen