From PA0SE
Gamal Soegioeno wrote:
Hello all,
does anyone of you have experience with EZNEC modelling software?
As far as I know, this is the only software (except for the original but
cumbersome NEC) capable of modelling the ground influence on
antenna feedpoint Impedance as well as on far field diagram AND
incorporating the conductor conductivity.
Most other programs account for ground influence on far field diagram,
but not on feed impedance, conductor losses are omitted.
It might be worthwhile to simulate antenna arrangements with EZNEC,
using an elevated Radial System. Radials need not have resonant
length, but might be "lengthened" by a radial loading coil in addition
to the vertical radiator's loading coil.
73 de Gamal
Dear Gamal,
I use NEC/WIRES by Brian Beezley, K6STI. It uses real ground also for
computing feed point impedance. But it cannot handle antennas fed against
ground, like Marconi's. Antenna Optimizer by K6STI can do that but assumes
perfect ground for impedance calculation. Both programs also take care of
wire losses.
I see no more advertisements by K6STI so perhaps he moved out of the
business. Together with PA0KSB I did some modelling of mobile antennas,
PA0KSB using EZNEC and I used K6STI's software. We got the same answers but
I have the impression that EZNEC is easier to use. If I had to buy now I
would go for EZNEC. But mind that it does not work for the surface wave. See
an earlier e-mail from maker W9EL to me that I have put on the reflector.
Only the expensive professional versions of these sort of programs provide
the surface wave.
73, Dick, PA0SE
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