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Spike[_3_] · November 30th 15, 05:35 PM posted to uk.radio.amateur,rec.radio.amateur.antenna

On 29/11/2015 23:24, wrote:

OK, I added radials for a total of 5 in a 45 degree spread and optimized
for minimum reactance.

radiator: 203 inches, radial: 186 inches, R: 52.4 Ohms, X: 0.4 Ohms

SWR: 1.1, Maximum gain: -.18 dBi in the direction of the radial and an elevation
angle of 30 degrees, Reverse gain: -3.7 dBi

Note with one radial the F/B ratio is about 5 dB and with five radials
it is about 3dB.

About the only thing I can see worth noting about this antenna is that
it shows more radials are better, but everyone already knows that.

Imagine a case whereby someone digs up the soil around the base of a
vertical antenna, a couple of feet deep and as far out as the antenna is
tall. Into this they mix 2 percent of high-aspect-ratio thin conducting
fibres, say about a foot long, and then replace the soil. 2 percent of
conducting fibres in an essentially non-conducting medium is about the
minimum proportion necessary to reach the percolation threshold..

What results from your modelling exercise do you get in this case?

--
Spike

"Crime butchers innocence to secure a throne, and innocence struggles
with all its might against the attempts of crime"

- Maximilien Robespierre