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Re: Topband: T - vertical improvement

To: Roy <royanjoy@ncn.net>
Subject: Re: Topband: T - vertical improvement
From: DAVID CUTHBERT <telegrapher9@gmail.com>
Date: Wed, 22 Jul 2009 05:38:43 -0600
List-post: <topband@contesting.com">mailto:topband@contesting.com>
The radial system you have will be fine. What you give up is matching
simplicity. The T will need a base series capacitor as a minimum and an
L-network if you like a 1:1 VSWR. At 1.5 kW the 370 pF cap will see 10 kV
RMS. You are looking at a vacuum variable capacitor.


    Dave WX7G

On Tue, Jul 21, 2009 at 8:01 AM, Roy <royanjoy@ncn.net> wrote:

> "A couple questions for the group....
>
> 1.  Supposedly I will end up with higher radiation resistance and
> efficiency, and I assume higher effective radiated power.  But what am I
> giving up?"
>
>
>
> Current maxima in your radials moves farther out from the feedpoint
> location
> than with a quarter wave antenna. Therefore you need longer radials.
>
> 73,   Roy    K6XK
>
>
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