Thread: Dish reflector
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Old April 22nd 09, 06:29 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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On Apr 22, 11:58*am, Cecil Moore wrote:
Roy Lewallen wrote:
If you look at the transmission line
properties of a vertical, you see that the two conductors (the antenna
and ground plane) get farther and farther apart as the distance from the
feedpoint increases. This behaves like a transmission line whose
impedance increases with distance from the feedpoint and, in fact, a TDR
response shows just this characteristic.


So what? An ever increasing Z0 does not change the
basic characteristics of a standing wave antenna, one
characteristic of which is: The phase of the current
relative to the feedpoint current phase changes by
a minuscule amount. So exactly how did you use that
current to measure and calculate delay???

I've never seen an attempt at
simulating it with distributed resistance, ...


Then, just as I suspected, you have never looked at my
web pages. Radiation "loss" can easily be simulated by
resistance wire. Please download

http://www.w5dxp.com/stub_dip.EZ

and alleviate your ignorance.
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com


Anybody got a copy of the two articles that Roy alluded too
I would really like to read them
Regards
Art