Dear J,

On Fri, 7 Jan 2005, J. Allen wrote:

Elnec shows the radiation resistance of the antenna with all resistances set to zero, to be about 0.02053 Ohms.

It seems to be very strange. Simple formula for top
loaded vertical R=1600(H/lambda)^2 yelds about 0.16 Ohms if H=20m. Though
it is more resonable then 0.02 Ohms. Are You sure there is no mistake in
elnec modeling? Number of computer experiments with NEC done by me
for different antennas on 136 kHz yelds results very close to this simple
formula.

73 de RA9MB/Alex
http://www.qsl.net/ra9mb