Jerry,
You supplied food for thought, but I'm looking for a simpler answer!
My antenna is a long way from the iron core of the earth, so that's
not an issue here. And I am only concerned with the near-field -- the
losses due to the currents in the dielectric under my antennas.
All I want to know is why my simple counterpoise seems to work better
than expected. Is the particular earth composition at my location a
contributor to this behavior? If it is, then I may elect to install a
modest (and inexpensive) ground system under my permanent antennas.
If not, I will accept my good fortune with the simpler antennas,
install a much more extensive ground system under the new ones and
anticipate even better performance on the low bands.
Gary, K9AY
----------
>Gary,
>
>There isn't any program I've used as yet that will model the earth
>properly. And thats as it should be to the large degree in my opinion.
>When talking about the low bands were incapable of more than near field
>ground improvements. The antenna sees it's environment as much larger
>as it should be. A program that helps you see it better is called Ytad.
>The earth has an iron core base. As such it cannot become insulator like
>to the antenna nor disappear. Except only possibly to a degree in the
>near field. Out beyond the radial system in theory for instance it
returns.
>And even my last statement is full of it unless the radial system is a
solid
>sheet of conductor. Anyway, it's better for you to look at the earth
>as being primarily consisting of near and far field effects on the
>antenna where the near effect our impedance matching concerns as well as
other
>issues. And the Far Field which actually define the antenna's own
personality
>modifications likewise. You only have limited control of the near field
>at best.
>Thankfully thru mathematics we can always return to freespace where we
>aren't taxed by any real estate owners, fault lines, oceans, lakes, trees,
>varmits, ect... Thankfully our planet is under constant geological and
>biological, also manmade change. Hope this helps you out?
>
>
>73, Jerry krr2ak@juno.com
>[text|uuencode|59kb ea]
> 'Y2K ? Because 1k is 3 decibels down in amplitude. 9991 krr2ak'
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