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Old July 18th 03, 01:54 PM
Tarmo Tammaru
 
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"Roy Lewallen" wrote in message
...
Most simple derivations for the input impedance of a dipole assume it's
infinitely thin.


That is why I used #30 wire



The general problem of a dipole made from wire of
finite diameter is a lot tougher, and is the topic of the papers by the
authors I listed in another recent posting. With EZNEC, you'll find that
the dipole impedance will continue to change as you make the wire
diameter smaller and smaller, until it gets too small for the program to
handle at all.



When I switched to #14, the impedance did not change more than a few tenths
of an Ohm. However, resonance went down about 10 KHz.

BTW, when I took my first Junior level EE Fields & Waves course I asked my
prof about the same question that Slick brought up. Was convinced that 300
Ohm TV antennas were really 377 Ohms!

Tam/WB2TT