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Old March 24th 09, 12:39 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
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Default colinear representation in NEC

Owen Duffy wrote:
The feedpoint impedance looks like it might provide a hint as to whether
currents are actually in-phase.


At a 1/4WL monopole's resonant frequency, the forward antenna
current and reflected antenna current are in phase. The two
component voltages are 180 degrees out of phase. The feedpoint
resistance is [|Vfor|-|Vref|]/[|Ifor|+|Iref|] where these are
antenna voltages and currents on a standing-wave antenna.

If the feedpoint impedance is purely resistive it appears
that the two component waves must be in phase or 180 degrees
out of phase.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com
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