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Old December 29th 08, 09:08 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 transmission lines and SWR and fractional wave antennas

On Dec 29, 1:14*pm, Cecil Moore wrote:
Art Unwin wrote:
So one acknowledges the presence of a capacitor at the end of a
radiator


Let's use IEEE definitions to avoid confusion. A "capacitor"
is a physical component that exhibits capacitance. Capacitance
can be exhibited without the existence of a physical lumped
component. At the end of a radiator, we would have a
distributed capacitance, not *a* lumped capacitor.


No Cecil. We are at the end of the radiator and there is no eddy
currents in front.
Ther apparently is a gap between the outside of the radiator end which
some see as a capacitor
( tho I see nothing that suggests that as yet) If one accepts a
capacitor as distributed then I will go along with that
but that alone cannot stop the flow of current.
Regards
Art





And
actually, it is not only at the end since it is "distributed".
In fact, an antenna element can be modeled as a distributed
RLC network where the R includes all "losses" including radiation.
--


I would love to see that circuit in its entirety since it will show
the points of collision


73, Cecil *http://www.w5dxp.com