I'm not sure about the rules regarding a loop antenna but I have a full-wave
vertical loop I've been using on 40 meters for years. My friend Steve K9AN
put up one for 80 meters once. He has a bigger yard.
:-)
The loop I'm using has vertical sides about 12 feet in length ahd horizontal
sides about 58 feet in length. I've modeled it on NEC2. The pattern is sort
of bean-shaped, with the lobes perpendicular to the loop. NEC2 says it has
about 5.8 dB gain over a dipole in those directions. Off the ends, not so
much gain.
You can think of the active part of the antenna essentially as two phased
verticals. The 12 foot vertical lengths do most of the low-angle radiation
and the horizontal lengths do the phasing of the vertical lengths.
73, Zack W9SZ
On Fri, Jun 4, 2010 at 2:32 PM, Hank Greeb <n8xx@arrl.org> wrote:
>
>
> Also, I'm thinking of putting up a full wave loop on 80 metres at about
> 35 to 40' high. Would this be considered a multi-element antenna if I
> used it on 40 metres? How about 20/15/10? I haven't bothered to
> research the directivity of a multi-wave loop, but I do remember vaguely
> that one gets directivity and gain, and the radiation angle gets lower
> as the length of the loop in wavelengths increases.
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