Probably a stupid question, but...
On Thu, 27 Sep 2007 09:52:39 -0500, "Dave" wrote:
When you say that the cutaway is the feedpont of the antenna, does that mean
it is where the received signal enters the antenna? And the feedline is
where it is carried to the receiver?
Hi Dave,
The single turn, shorted loop with an open shield is merely a
convenient construction. It brings nothing new to the table of RF.
Owen's page pretty much describes it all, but there's always the
off-chance it needs to be said again.
The gap is the feedpoint driving your transmission line.
The gap and driveline drop must be at the points shown for symmetry to
insure balance.
Shielding does nothing but describe a balance. You can as easily
remove the shield and obtain identical performance IF you guarantee
balance. This was done for decades before coaxial cable was common.
The gap, the short, and the shield all lend the aura of "magic" to an
otherwise conventional loop. Being "magic" gives rise to ridiculous
claims applied to it. Being "magic" divorces logic from the design.
That loss of logic begins to migrate among the "magic" crowd such that
they come up with useless antennas.
73's
Richard Clark, KB7QHC
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