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Owen · September 30th 10, 07:24 AM posted to rec.radio.amateur.antenna

On 30/09/10 12:05, wrote:
....
So being as the increase is fairly small at such low heights
in wavelength, it is probably practical to just bury them so
people won't trip over them.. :/
If tripping is no issue, then it might be worthwhile to get
the slight edge in performance. But the increase over buried
will be fairly small with them only 100mm up.

I am interested in the electrical performance rather than trip hazard.
Once electrical performance is known, issues like trip hazard, mowing,
rock etc can be dealt with for each application scenario.

So, back to the electrical performance, do you have measurement data, or
can you refer me to articles that contain sound objective measurement
data that would suggest that my NEC4 model is not valid.

If I have modelled the situation correctly, the models suggest that the
portion of energy lost in heating the soil drops very rapidly with
increase in height from zero to just tens of mm, and with very little
change to the pattern distribution.

Owen

PS: I perhaps need to clarify the meaning of 'efficiency' in my post, I
mean the total power radiated in the far field in the hemisphere,
divided by the power input to the antenna.