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jawod · July 24th 06, 04:17 AM posted to rec.radio.amateur.antenna

wrote:
jawod wrote:

I am considering building the Louisiana loop shown in this month's QST.
It is basically an inverted delta loop. I don't know if I can model
it on EZNEC (I guess I can...but I've only progressed through a dipole
or two).

I actually intend to string it up among some trees in the backyard in a
sort of temporary fashion.

Realizing the directionality involved, I will aim it toward Asia over
Alaska.

Now, any caveats or recommendations or ? before I embark on my first
antenna build?

I don't at present even know the feedpoint impedance but I intend to use
RG8U for feedline if that's possible. There is no mention of an UNUN or
Balun in the article.

What do youse think? Thinks?

John
AB8WH

PS, I'll give the hoberman sphere a rest for a while (hi)

Hi John, The model does not account for the metal tower right in the
middle of the delta loop. It will have some effect on the feedpoint
impedance, as well as the pattern.

If I were to string it up among trees, I would go with a standard (not
inverted) delta loop configuration. According to the article, it gives
about 1 db more forward gain at an elevation angle that might favor dx.
You won't have to worry about a tower messing things up either.

As for feeding the loop, consult the ARRL Antenna book for the various
methods. For a single band Quad or delta loop, I would use a series
transmission line matching transformer. Thats what I think.

Gary N4AST

Thanks for your input, Gary!