Re: NEC-LIST: ground conductivity of grassy soil

> can the ground
> conductivity at standard AM broadcast band frequencies be improved near a tower
> if dry, barren earth is enhanced with a crop of live, green grass that is kept
> moist with an agricultural sprinkler system? g

I'm wondering if your question might be about AM (MW) broadcast stations.
If so, I reckon all if not the vast majority of them (in the U.S., at least)
have an extensive ground radial system in place (they'd be foolish not to),
and then the question is whether the topsoil helps much above what the
radials already provide.

(I used to work at an AM station located on top of a hill ... oddest place
to put the transmitter, especially with many marshes and cranberry bogs
within a few miles of that site. The antenna tuning did shift slightly
whenever it rained... It had a good grass cover, though I think that had
more to do with the owner's farm animals that he kept up there.)

> Can someone explain me how I can transfer this E/Eo into a
> permittivity e_r?

Unless we are talking about different abbreviations, E (epsilon) is the
actual permittivity, Eo is the permittivity in a vacuum, so E/Eo would
equal the relative permittivity Er (e_r?).

Andy

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