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Re: [TowerTalk] Coaxial Moxon

To: "David J. Sourdis" <>,
Subject: Re: [TowerTalk] Coaxial Moxon
From: "Dan Zimmerman N3OX" <>
Date: Sun, 3 Aug 2008 21:07:07 -0400
List-post: <">>
> A quarter wave coax, shorted at the end shows an infinite impedance.Is it
> possible what is described in the link?

A coax just a little bit shorter than a quarter wave shows a VERY quickly
changing inductive reactance ... so you can change the stub length +/- a few
centimeters and find the exact value of reactance you need to load the

But, it's VERY lossy to operate a stub near resonance as a reactance.  I
estimated something like Q = 1 or Q= 5 for the "quarter wave" (actually a
little shorter) stubs in that antenna, and a model of it seemed to suggest
that the gain would be *negative 10dBi* and it would have zero F/B ratio.

You might look at as well.


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