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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