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[Towertalk] C31XR & guy wire detuning

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Subject: [Towertalk] C31XR & guy wire detuning
From: Sylvan Katz <jskatz@sk.sympatico.ca> (Sylvan Katz)
Date: Tue, 23 Jul 2002 13:47:46 -0600
Hello All

I am trying to solve a guy wire problem - they seems to be detuning my
C31XR. Last year when I installed the antenna I found I could not get the
swr down to the spec level on 15 and 20. Natan suggested that I my guys
could be detuning the XR. This summer I inserted insulators right at the top
of the tower. This brought 15m right on spec! Great!

 I am still having problems on 20m - the minimum swr is about 400 khz too
high. The bottom sections of each guy is about 54' long. Natan suggests that
the capacitance caused by the insulators and subsequent following wire
lengths can easily move the resonance of the 54' to a length near 62 feet
which is nominally a full wave resonator on 20 meters.

I want to break the 54' sections into two segments each. My question:

What should the lengths of these two sections be to minimize their
interaction with the C31XR?

.. sylvan

ps - please do not recommend the use of Phyllistran -- it is too costly to
have it shipped here :)


Ô¿Ô¬
----------------
Sylvan Katz, VE5ZX
Saskatoon, SK
"A Novel Perspective of Amateur Radio Contesting" at
http://www.dynamicforesight.com/~ve5zx


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