A quick modeling job on the superloop shows that the gain in its best
direction is very close to that of a dipole at the height of the top
wire on both 80 and 40 (probably within 1 dB). Maximum gain is
perpendicular to the plane of the loop on 40 and 80. The SWR bandwidth
on both 40 and 80 is much narrower than that of a dipole.
On 20 meters the pattern changes to a 4 lobe pattern with maximum
radiation at about 45 degrees to the plane of the loop. There is a null
broadside to the loop. The lobes are skinny (beamwidth about 35
degrees). The gain in those lobes is about the same as a dipole. The
SWR on 20 and 15 is very high, so if you feed it with coax there will be
a lot of feedline loss.
On 15 meters the pattern turns into lots of lobes and nulls and the gain
of the lobes is much less than that of a dipole. It looks poor on 15.
Jerry, K4SAV
KI9A@aol.com wrote:
> Gang-
>
> I've googled this, and have no real answer, so, I turn to the real
> knowledge base of the hobby--you guys!
>
> We are planning on a FD effort, with a local club this year, and are
> considering antennas. We are using available trees in the 40-50' range, and
> maybe a simple push up pole or 2. No tower, no yagi's. All wire.
>
> I want something with a bit of gain.
>
> Conventional thinking ( and good results in other years), I am thinking of
> a simple open wire fed 80 meter dipole for all bands. But, I am thinking
> of building a Radioworks cloned Superloop.
>
> Seeing that this acts as a bi-square on 40, it should show directivity and
> slight gain off the ends. Here is the big question: 1) In real life,
> does it? 2) Has anyone ever modeled this antenna? Results on 40/20?
>
> I guess my concern is it is broadside E/W, I am in Sw Illinois, which is
> good. But, on 40, if it fire N/S, that's not so good.
>
> Also, any other wire antenna ideas? I kinda want to be heard on the west
> coast, on 40 at night, plus, be good to the east.
>
> 73- Chuck KI9A
> **************Worried about job security? Check out the 5 safest jobs in a
> recession.
> (http://jobs.aol.com/gallery/growing-job-industries?ncid=emlcntuscare00000003)
> _______________________________________________
>
>
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