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Topband: Elevated vs Buried Radials

To: <topband@contesting.com>
Subject: Topband: Elevated vs Buried Radials
From: "Larry Schimelpfenig" <k7sv@adelphia.net>
Date: Sat, 5 Mar 2005 15:15:06 -0500
List-post: <mailto:topband@contesting.com>
Ken said:

>I would like to see comparisons wherin the total tower
>height remains constant, and the feedpoint height and >radial system height 
>and number of radials are the >variables.

Maybe I should get off my duff and get into modeling myself, but until I 
do.....

I'd like to know if anyone has included the gull wing effect of using 
elevated radials with a ground mounted vertical in the model?

I used to use a 40 meter extended double zepp with 60 feet of ladder line 
coming straight down a tulip poplar into the shack fed as a T on 160. It 
worked against two quarter wave radials that were about seven feet off the 
ground. As civilization (?) encroached I had to go to an inverted L with 60 
feet vertial and about 110 feet horizontal fed against five quarter wave 
radials about ten feet off the ground (gull wing).

Comparing the two seems to gel with everything I've read. The inverted L 
seems better on the closer in stuff while I sense that the T was better on 
the longer stuff.

The difference in the radial configuration between the two, is the T was 
terminated at an L network about five feet off the ground and the radials 
slowly increased in height from the five foot level to the seven foot level. 
On the inverted L the radials begin at a capacitor one foot off the ground 
and extend up and out at 45 degrees. They extend out until height is about 
10 feet and then countinue at that height to the ends.

Following some hints on the reflector, I'm looking at various means to go 
from asymetrical back to symetrical top loading.

Rather in line with a question that was asked earlier, I'm trying to figure 
out if I would gain anything by shortening the vertical so the base would be 
at the same level as the  elevated radials, to eliminate the gull wing 
effect.

73 de Larry K7SV

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