[Elecraft] KX1: requesting recommended wire antenna lengths advice

[Walter Underwood]

The “random wire” lengths are actually non-resonant lengths, especially avoiding high-impedance half-wave wires.

Balun Designs has a nice chart of the SWR for each band with their 9:1 balun. These lengths are theoretical, because performance will be quite different over a parched granite peak vs a salt-water swamp. You may need to try different counterpoise lengths to tune the system.

http://www.balundesigns.com/content/Wire%20Lengths%20for%209-1%20ununs.pdf

wunder
Walter Underwood
wunder at wunderwood.org
http://observer.wunderwood.org/  (my blog)

On Apr 19, 2015, at 3:08 PM, Pat Ring <pat.ring1 at gmail.com> wrote:

> Hello.  I researched this, eh, pretty thoroughly, but I keep running into a
> little problem with the recommended lengths for direct-fed antennas.  The
> KXATU guides recommend a 24'-28' radiator and a 1/8 wave
> ground/counterpoise, but I have seen 28' and 41' recommended as well (some
> with recommended radials and some without).  The 24' wire tuned up fine on
> 20m and 30m, around 1.2:1, but I can't get an KX1ATU lower than about 8.9
> SWR on 40.  Am I missing something obvious, or should I continue to
> experiment?  I've only tried that ATU about three times on 40M because that
> SWR seems pretty high to me and has to be tough on the kit.  I am reluctant
> to continue to try anything in this range now.  I don't really want to take
> coax on the road with me, and 20m and 30m are ok, but I would like to
> participate in the 4sQRP on 40m when I am on the road this week.  I would
> appreciate your advice.  Thanks.  Pat NQ0N
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