Thread: Dish reflector
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Old April 24th 09, 02:57 AM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
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Default Loading coils: was Dish reflector

On Apr 23, 7:40*pm, Jim Lux wrote:
Roy Lewallen wrote:

Regards,
Steve G3TXQ


Yes, you would see this in the real world. EZNEC does a very good job of
modeling a wire antenna with a loading coil, provided that you model the
coil as a wire helix rather than lumped "load", and you can trust the
results. As I've implied, a lumped load is quite a good model for a
physically small, essentially non-radiating loading coil like a toroid
on a magnetic core.


Roy Lewallen, W7EL


which makes perfect sense...
NEC is a MoM code and is ideally suited to calculating the current
induced in one wire by the currents in other wires. I should think it
would do an excellent job modeling a air core solenoid, especially if
the wire diameter is small compared to the spacing between turns,etc,
assuming that you don't get into numerical precision problems.


If eznec does not take into account dielectric loading then the
application is not in equilibrium and thus Maxwells laws are not
applicable. Maxwells laws are based solely on the presence of
equilibrium or accountability of all loads applied which when all are
added equals zero per Newtons laws.
Regards
Art