TopBand: One use for the magnetic radiator

[Eric Gustafson]

>From: Tree  N6TR <n6tr@teleport.com>
>Date: Tue, 16 Sep 1997 08:09:31 -0700 (PDT)
>
>It has been suggested that one loop will work just as well as two, and
>certainly easier to put up.
>

We built both versions of this antenna here a few years back.
Both of them performed well.  However the single loop was _far_
easier to match.  It matches 50 ohms directly when constructed
with the correct aspect ratio. The single loop had slightly
better on axis field strength as shown by a simple diode/meter FS
indicator a few hundred feet out.  This may have been due to
lower conductor losses, lower matching network losses, higher
pattern gain due to vertical elements being farther separated, or
a combination of all of the above.

NEC-2 modeling accurately predicted loop dimensions and feedpoint
impedance for the single turn loop.  Dimensions were a bit off
for the two turn version.

I have modeled but not yet built a "Bowtie" version of this
antenna.  The idea is to minimize the volume of space where the
near field e-field is stored to minimize local losses.  If a
local ham "bites" on this design and we build one, I'll report on
it here on the topband reflector.

73,  Eric  N7CL

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