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Old January 28th 13, 04:15 AM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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First recorded activity by RadioBanter: Jun 2007
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Default 2m antenna home brew??

On Sun, 27 Jan 2013 22:34:35 -0500, "Ralph Mowery"
wrote:


"Jeff Liebermann" wrote in message
.. .
On Sun, 27 Jan 2013 10:53:41 -0500, "Tom" wrote:

But I want to hear some positive ideas. How can I make this work for 2m
and
70cm. I don't want a 10m omni.


You would probably do better loading a step ladder. However, if you
insist, you can load just about anything if you can find a 50 ohm tap
point with a gamma match. Attach a connector ground to the bottom of
the element with a hose clamp. Put another hose clamp further up the


The step ladder probably will work just as well as the full wavelength
vetical. More than likely the radiation patern will be vertical and only
good for working OSCAR.


Well, the step ladder antenna came from what appears to be a
fabrication, where a loaded step ladder allegedly won an ARRL
sponsored antenna construction gain competition. I have my doubts,
but it was a good story. In the best Mythbusters tradition, I
produced a crude model of a fiberglass extension ladder section with
4NEC2 to see what could be done. I selected fiberglass because the
insulating fiberglass would not short the aluminum ladder rungs. At
this point, it's only a model and I haven't actually tested more than
the driven element matching.

If you don't mind, I would like to keep the details of how I did it
secret as I was considering writing an article on the topic.

As it is well known you can match just about anything to 50 ohms but that
does not mean it will radiate or atleast radiate in a desirable direction.


Yep.


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Jeff Liebermann
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