Tim,
I have experimented (successfully) with two sets of loops spaced 1/4-wave. They
were wired to be in phase when broadside, and 180 deg. (phase reversed) when in
endfire mode. Endfire could be improved with different phasing, but the 0/180
setup is very simple.
When broadside, the main lobe is narrowed somewhat, with better S/N but not a
big difference to the ears.
Endfire, you get the same F/B as a single loop, but add two very deep nulls off
the sides. Since the null is also overhead, the array now rejects high angles.
The pattern improvement is quite dramatic in many cases.
73, Gary
K9AY
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Date: Mon, 9 Dec 2013 14:14:22 +0000
From: "Shoppa, Tim" <tshoppa@wmata.com>
To: "topband@contesting.com" <topband@contesting.com>
Subject: Topband: Quarter-wavelength patterns available
I am an alligator since adding an amp to my station and need to improve 160M
receive abilities.
I have a very odd shaped suburban lot but I do have a quarter wavelength on
160M available in roughly the NNE-SSW direction.
The corners of the lot have a lot of brush and trees and are actually pretty
good opportunities for supporting K9AY loops in. I have a near infinite supply
of bamboo poles from neighbor's overgrowth I might be able to use as supports
too. I already have a K9AY loop in one corner of the lot but would like to
improve things.
What patterns would be available to me given the roughly quarter wavelength
spacing? Most desirable directions are NE to EU and W to California.
Tim N3QE
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