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Old September 29th 07, 04:21 AM posted to rec.radio.amateur.antenna
K7ITM K7ITM is offline
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First recorded activity by RadioBanter: Jul 2006
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Default "Quarter wave ground mounted radials are a waste of wire."

On Sep 27, 7:45 am, John Ferrell wrote:
On Sun, 23 Sep 2007 12:46:30 -0400, "Rick (W-A-one-R-K-T)"

wrote:

I just read the following on one of the mailing lists I subscribe to:


"Quarter wave ground mounted radials are a waste of wire and a hold over
from the olden days. Check the antenna handbook, the new philosophy is
more and shorter. The thing is that the bulk of the energy from the
vertical antenna is near the base of the antenna and this is what you are
trying to capture. A quarter wave radial sounds logical but the planet
will detune it so a quarter wave means nothing to the current."


What say you all?


Read this and see if you really want to know more.

http://www.bencher.com/pdfs/00361ZZV.pdf

A challenge to all you experts out the
Can you find anything you disagree with in this document?

John Ferrell W8CCW
"Life is easier if you learn to
plow around the stumps"


That seems a very practical ap note. But since you issued the
challenge, I'll say I disagree with the wording of an early sentence,
where it says that ground return currents are "greatly attenuated" if
they come through lossy earth. Clearly, the current is not
attenuated; the current is what it is. However, the current through
lossy ground causes power dissipation (and loss of radiated power) in
the ground.

I think the meaning is clear, but the wording would not pass muster
with a good technical editor.

Cheers,
Tom