On Wed, 14 Oct 1998 07:55:02 -0400 (EDT), "L. B. Cebik"
<cebik@utkux.utcc.utk.edu> wrote:
>The problem of modeling linear loads in NEC (-2 or -4) is multi-faceted.
>First, both versions of NEC have difficulties with angular junctions
>involving materials with different diameters. Note that tapered diameter
... very careful long statement on problems modeling LL antennas ...
Thank you for the post.
Still, for the casual user, the solutions are out-of-reach. Let it
suffice to say that it takes a *very* well informed modeler with an
array of tools to begin to attempt LL modeling, and even then it's a
snake pit.
I think the variegate state of modeling LL shows in the kinds of posts
one reads about results with the various kinds of shortened antennas
for 20/40/80, 40m especially.
At the far opposite, note what the modeling has done to perfect design
of various fullsize 2 el yagi configurations, eg F12 C3 types and
such, to a point that front-to-back considerations mainly recommend
that third element.
It may very well become (if not already) that reliable modelability of
a design is the first and most important element of it's commercial
feasibility.
73, Guy.
Guy L. Olinger
k2av@qsl.net
Apex, NC, USA
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