Richard Fry wrote in
:

On Oct 1, 12:45 am, Owen Duffy wrote:
....
Using NEC-4 to incorporate buried (or elevated) radials into the model
should show groundwave fields within 1 km of the monopole that are
very close to the theoretical maximum for the applied power when
radiated along a perfect ground plane, if the model is optimal, and
accurate.

It may do, I can not comment. My interest is for an antenna for sky wave
path, and I have not explored ground wave performance.

In the cases of 32 buried radials and three elevated radials, the
patterns are similar, efficiencies are similar, and maximum gain is
similar. Reducing the number of buried radials degrades its performance
significantly.

The elevated radials configuration allows a shortened radiator with
capacity hat with negligible degradation in performance. I haven't
modelled the same thing over buried radials, but I expect performance
degradation would be significantly worse.

Owen