On Sun, 2 Sep 2001 "Tim Makins, EI8IC" <ei8ic@eircom.net> writes:
>
> I feel the topic of horizontal loops should be expanded on here.
> They seem a cheap and easy-to-construct antenna, which can be
> supported from 3 or 4 wooden poles, 20-30' high, in the corners
> of a small lot. The wire can be of a small gauge, and hence almost
> invisible, as long as you don't mind repairing it after occasional
gales,
> ice or bird-strikes. I have heard of one Scottish station using two
loops,
> one above the other, on the same poles, and claiming very good results
> QRP to VK-land.
>
> Who else has actually used a horizontal loop on the low bands, and
> what are your comments ?
>
> Tim www.qsl.net/ei8ic/
Sorry to disagree Tim, but a LOW horizontal 1WL loop is not my
idea of a good DX antenna. It IS a good high angle radiator for
local coverage. On harmonic frequencies, each side behaves
as a phased array of dipoles or long wires, depending on how
the sides compare to one wavelength at the frequency of interest.
A 2WL square loop (1/2 WL on each side), fed on the center of
one side, is an interesting antenna. It acts as two pairs of half wave
dipoles spaced 1/2 WL and fed out of phase. Each pair of opposite
half waves gives a bi-directional figure 8 pattern resulting in a nearly
omni-directional horizontally polarized pattern for the square loop.
If mounted at 1/2 WL high it is an effective and useful antenna.
At 20 or 30 ft on 80 or 40M, it SUCKS compared with a higher
dipole or good vertical.
Regarding wire size, anything smaller than #18 copper based wire
is subject to breaking readily from falling limbs or ice loading.
Tom N4KG
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