[Elecraft] Re: Elecraft digest, Vol 1 #374 - 54 msgs

[Jack Brindle]

On Monday, December 16, 2002, at 19:37:28 PST, "rich a." 
<rckchp@comcast.net> wrote:

> I put up a "Loop Skywire" today  (  
> http://www.arrl.org/members-only/tis/info/pdf/8511020.pdf  ). Mine is 
> sort of a narrow rectangle rather than a square loop....I don't have a 
> long tape measure so the size is a very rough estimate.....approx 170' 
> long by approx 50' wide (approx 440' total). One corner is up approx 
> 35'....the nearest opposite corner is approx 20' up.....then it slopes 
> down to approx 15-20 ft at the far ends. Its what fits with the trees 
> I have on my property.
>
> The feed point is approx 45' from the corner on one of the long legs. 
> I'm using rg8x, no balun. I didn't even try to "model" this but I just 
> worked Boliva and Argentina (Tierra del Fuego) on 20m, both new 
> countries for me, using my K2 with autotuner at 5 watts ssb, got 5x5 
> reports....so I'm doing the happy dance, as I had nothing to use on 
> 20m before today. Mojo at work? I think yes!! :-) <g>
> I'll be trying it on 80 and 160 tonite but may have to adjust the feed 
> line length to get a better match....the way it is I only get 4.7-1 on 
> 160, but it does 1.2-1 on 80.

Now remove the coax and feed it with twinlead or open-wire feed. Bring 
the twinlead into the shack, and use a Balun _AT_ the K2/KAT2. You 
should be able to tune the antenna up on any frequency and have it work 
quite well. The feedline won't radiate (as the coax certainly does now) 
and you will be very happy.

I'm running a 260-foot horizontal triangular loop antenna (because 
that's about all my city lot will let me do) with very good success. It 
is fed with 1" open-wire feed, and a homebrew  "swinging-link" antenna 
tuner. Someday soon (when I get other projects out of the way) I'll 
figure out how to automate that sucker...

-Jack Brindle, WA4FIB
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