Topband: Ground mounted 1/2 wave

[DAVID CUTHBERT]

On Mon, Dec 17, 2012 at 8:41 PM, Carl <km1h at jeremy.mv.com> wrote:

>
> Subject: Re: Topband: Ground mounted 1/2 wave
>
> **  All that means is that the elevation peak of the wave as seen in the
> typical 2D plot increases by .38dB and as expected. It does not say what
> happens from that peak down to zero elevation which is what 160M DXers care
> about.
> What is the FS at 5, 10 degrees when going from a ground rod to a full
> bore radial field over a wide range of ground conductivity?
>
> Carl
> KM1H


Yes, it does say what happens from that peak down to zero elevation. It
says that the signal increases by 0.38 dB.

To test this I ran two EZNEC simulations. One is a 90 degree vertical over
thirty 90 degree radials over medium ground. The antenna is driven with 1
kW and the E-field at one mile is recorded from a height of 10' to 1000'. A
second 90 degree vertical over four 23 degree radials driven with 1 kW and
the E-field at one mile is recorded from a heights of 10' to 1000'. *The
difference in E-field AT ALL ELEVATIONS is 0.86 dB*.

   Dave WX7G

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> ______________________________**_________________
> It is undesirable to believe a proposition when there is no ground
> whatsoever for supposing it is true. — Bertrand Russell
>