Al Williams wrote:
> Our club is planning to use an elevated vertical for fd 40 m. I have been
> tasked to use EZNEC to determine length of the vertical and radials given a
> feedpoint 10' above ground.
>
> EZNEC reports good vswr with a 4" alum pipe vertical element 33.1' and
> radials 32.5' of #22 wire.
>
> However the elevation pattern and gain using real ground shows virtually no
> difference with 0,2,4, and 8 radials. The source impedance jumps from highly
> reactive with no radials to 50 ohms mostly resistive using two radials and
> lowers a bit using 4 and 8 radials.
>
> The pattern and gain being nearly identical no matter how many radials are
> use (including none) has me wondering if I have something wrong in my model?
>
> All comments appreciated, please.
>
> k7puc
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I think you are confusing buried radials with elevated radials. The only
time you start seeing a drastic change when adding lots of radials is
with ground mounted verticals utilizing buried radials. With elevated
radials about two per band seems to work just fine
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