Tom:
Thanks for the clarification. I was thrilled that I had been able to
move the minimum SWR point into the sweet spot on 160M. I, therefore,
concluded I could do this for almost anywhere in the band (I might still be
able to, but not for the resaons I had thought - changing the resonant point
of the structure.)
Also, you may have missed a subtle point in my last e-mail - I'm going
to try loading the tower on 80 the same way - a shunt wire up another (or
maybe the same) tower face. I'll work with that arrangement for a while,
rather than trying your elevated-feed ground plane as I wrote in earlier
posts. I've been thinking about the radials for the elevated arrangement
and have concluded that that will take some maneuvering on the tower by
Yours Truly. Also, I have a small, heavily-foliated backyard and I'll have
to think about using loaded radials of some kind (maybe) to get the low-T.O.
angle radiation pattern of two in-line wires. Using the shunt wire is
easier mechanically and I want to compare apples to apples first (I now know
how to get a shunt wire to work), then move on to your design.
73 de
Gene Smar AD3F
-----Original Message-----
From: n4kg@juno.com <n4kg@juno.com>
To: TOWERTALK@contesting.com <TOWERTALK@contesting.com>;
SPELUNK.SUENO@prodigy.net <SPELUNK.SUENO@prodigy.net>
To: <towertalk@contesting.com>
Date: Thursday, March 07, 2002 11:54 PM
Subject: Re: [Towertalk] Trylon on 160M - Redux
>
>
>On Thu, 7 Mar 2002 23:07:06 -0500 "EUGENE SMAR"
>
>> This tells me that the TAP POINT determines the resonant freq of
>> this type of shunt feed; the cap value is determined by the length,
>> and thus inductive reactance, of the shunt wires.
>
>The RESONANT FREQUENCY of the ANTENNA is determined
>by the size and shape of the STRUCTURE.
>
>The TAP POINT has some complex IMPEDANCE with a REAL
>and REACTIVE component. The shunt wire and capacitor
>are tuned to reduce this reactance to ZERO. Calling this
>"RESONANCE" is a misnomer. It is MATCHED, not resonant.
>
>Tom N4KG
>
>
>
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