KX3 SWR meter (RF feedback?)

[Nicklas Johnson]

Hi all,

I'm currently on a trip and brought my KX3 and Buddistick with me.  I also
brought along my antenna analyzer.  As one does when relaxing.

The analyzer shows that the Buddistick is giving me <= 1.5:1 SWR across the
20m band, and I did a tuner memory clear (I'm using the beta firmware) and
fresh tune for 20m on the KX3.  It reports 1:1 after doing just a little
tuning up.  Receive sounds fantastic here in the middle of nowhere.

On transmit, however, the SWR meter on the KX3 is showing >=3:1.  The
signal seems to be getting out admirably; pskreporter.info shows I've been
picked up in Japan, Alaska and all the way to the east coast of the US.  If
I physically grab the shield of the antenna connector, the SWR meter drops
a little bit.  I wish I had brought my external SWR meter along with me for
comparison.

If I lower the power output to 0.3W, the SWR meter drops all its bars, but
when I increase it to 0.4W, it flickers a bit but goes up to >=3:1.

My question is this: could this be just an RF feedback issue due to the
relatively close proximity of the KX3 with the Buddistick?  The way the
coax routing worked out, I'm sitting only about 10-12 feet from the
antenna.

If so, aside from getting further away from the antenna somehow, are there
other suggestions of things that can be done in the field to work around or
mitigate the problem?

Thanks for any advice,

   Nick / N6OL

--
*N6OL*
Saying something doesn't make it true.  Belief in something doesn't make it
real. And if you have to lie to support a position, that position is not
worth supporting.
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[Nicklas Johnson]

I'm face-palming. I should have thought of that. Fortunately I did bring an extra length of coax and a barrel connector. I wonder if maybe I could leave that 25' length of cable coiled up just as it is (though it's closer to an 8" diameter) and see if the behavior changes.

Good call.  I'll try a few things.

   Nick

John Oppenheimer <[hidden email]> wrote:
>Hi Nick,
>
>Are you using a Balun of some sort at the antenna? If not, try a coax
>coil Balun with your feedline.
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[Nicklas Johnson]

John,

Thanks much for the suggestion.  10+ turns around a paper towel roll
completely cured the problem.  Glad I brought the extra coax and a barrel
connector with me!

http://i.imgur.com/ZJDFtCg.jpg

73 and thanks again,

   Nick


On 7 September 2013 10:51, John Oppenheimer <[hidden email]> wrote:

> Hi again Nick,
>
> A coax coil Balun works best if it's wound in a solenoid fashion as in
> the example.
>
> John KN5L
>



--
*N6OL*
Saying something doesn't make it true.  Belief in something doesn't make it
real. And if you have to lie to support a position, that position is not
worth supporting.
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