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Old March 18th 08, 05:56 PM 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 Antenna physical size

On Mar 18, 12:26 pm, Michael Coslo wrote:
Roy Lewallen wrote:
Mike Coslo wrote:
On Fri, 14 Mar 2008 11:57:41 -0700, Roy Lewallen wrote:


Richard Harrison wrote:
Build a small scale model that can be tested indoors and report its
characteristics. Antennas are scaleable.
That's more easily said than done. One of the critical characteristics
of a small antenna is loss. And to correctly replicate loss in a scaled
antenna requires scaling the conductivity of the conductors as the
square root of the frequency. To scale to a higher frequency requires
that the conductivity be better than the original. Unless the original
is made from lead and the scale factor moderate, this wouldn't be
possible.


If what I suspect is true, would not the coax also need to be scaled?


Dunno. What do you suspect?


I suspect that the antenna is a tuned circuit on top of coax, and it
needs that coax to radiate effectively. So just scaling the antenna
wouldn't translate to the same results?

- 73 de Mike N3LI -


If you are familiar with computor programming then why not model it
instead of repeating over and over again this transmission line
radiation theory.?