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Old January 14th 09, 05:23 AM posted to rec.radio.amateur.antenna
Frank[_9_] Frank[_9_] is offline
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First recorded activity by RadioBanter: Dec 2008
Posts: 23
Default Contrary current flow within a radiator


Frank, I am not saying he is not credible but he is part of the older
generation and there was not enough detail supplied to determine
whether I accept it on trust. When the antenna programs
throw out the yagi in favor of arrays or radiators in equilibrium form
should we throw it out in favor of conforming with the past? Yes,the
article is in line with what the older generation has lived with
but the new generation have more tools and information than the
present dying generation.
Problem with present day authors is up against the "publish or
perish" format regure references to prior papers in quantity to
provide legitamacy to any new papers, without which they will have a
hard time publishing. Greasing the wheels of fellow contributers or
white paper authors is much preferable to declaring those who judge
are in error. Frank, a lot of the theory of antennas is either based
on vanishingly thin radiators without regard to room required for eddy
field and in some cases with transmission lines where it is possible
to get three different current flows together with a closed circuit,
yet we are now protecting the idea of non closed circuits where the
current flow
is on top of each other. No wonder it is said over the last 100 years
that we don't fully understand radiation especially when it takes over
70 posts on how to make a cantenna from a panel of experts
Best regards
Art


I would hardly call the tools used in this simulation "Older".
Ansoft produces some of the most sophisticated, and up to
date FEM software available. I have seen Ansoft's HFSS
accurately model current flow through PCB vias, around an end-
launch connector at 20 GHz. CST Microwave also
produces high end FEM software. All the models are
done in full 3 D, with actual physical dimensions. This
FEM software started to apear about 10 years ago and
costs in the range of $40,000 to $50,000, with a $10,000
per year maintenance fee.

"Publish or perish" is usually applied to university positions.
It is doubtfull that too many people are able to pubish in
the Proceedings of the IEEE, or one of the IEEE Society
Transactions.