EZNEC can model radiating transmission line stubs made from either
parallel wires or coax. To do it, parallel wire lines have to be modeled
as wires, not with the non-radiating transmission line model. Radiating
coax is modeled with a combination of a non-radiating transmission line
model for the inside, and a wire to represent the radiating outside of
the coax. This technique is described in the EZNEC manual and
illustrated with the DipTL.EZ example file included with EZNEC.

There are some types of antennas which aren't possible to model with
NEC-based programs. An example is a patch antenna on a dielectric
substrate -- NEC and EZNEC have no way to model the dielectric.
Likewise, a "loopstick" antenna -- a solenoid wound on a ferrite rod --
isn't possible because of the ferrite and possibly because of the
exceptionally small dimensions (for one used at AM broadcast frequencies).

But most often when you see an antenna inventor or seller claim that his
antenna "can't be modeled" by NEC, EZNEC, or other programs, it just
means that modeling fails to show the extraordinary performance he
claims for it. That's simply a failure of the program to include the
effects of magical properties and wishful thinking in its calculations.
I've come to regard such claims as a red flag indicating a probable
exaggeration of antenna performance.

Roy Lewallen, W7EL

Bill wrote:
Cecil Moore wrote:
Bill wrote:
I have not seen a well described antenna that
could not be evaluated honestly by a person aware of antenna theory and
the modelling programs.
The Lentine (sp?) antenna, consisting of different lengths
of radiating transmission stubs proved impossible for me
to model with EZNEC.
--
73, Cecil http://www.w5dxp.com

Cecil- Obviously, you fit the qualifications I mentioned, and- just as
obviously, I did not know of that example. I need to do some homework.
Thanks-Bill