Thread: Dish reflector
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Old April 23rd 09, 11:11 PM posted to rec.radio.amateur.antenna
Owen Duffy Owen Duffy is offline
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First recorded activity by RadioBanter: Dec 2006
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Default Loading coils: was Dish reflector

"Tom Donaly" wrote in
:

....
not be easy. Finally, a modest question: if you have EZNEC, why would
you be wasting time with something inferior? The gold standard is the
gold standard.


NEC (in whatever form) might give a good estimate of the inductance of some
helices, although many practical inductors require smaller segment lengths
that would normally be advised for NEC models, but it does not provide a
good loss estimate in many interesting cases.

My post entitled was about that
topic, and apart from Jim's suggestion of a sensitivity analysis, there was
no solution to evaluating the effective resistance of an inductor of
closely spaced turns (so proximity effect is signficant) made from a
braided round conductor and with a thin dielectric jacket. All three of
these factors are, as I understand it, not modelled in NEC-2.

Owen