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Old May 5th 07, 04:30 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
Posts: 3,521
Default Laws, Statisitics, Lies, and the Damned TRUTH

I have succeeded in using EZNEC to model a coil sans
reflected current. Eliminating the reflected current
clearly shows the phase shift of the forward current
through the coil.

I modeled a 75m Texas Bugcatcher coil terminated in
its characteristic impedance of 2745 ohms at its
self-resonant frequency of 7.96 MHz which essentially
eliminated the reflected current. The 90 degree phase
shift at self-resonance is clearly visible. That EZNEC
file can be downloaded from:

http://www.qsl.net/w5dxp/coil505.EZ

Switch from 7.96 MHz to 3.8 MHz and change the load
from 2745 ohms to 1975 ohms. The phase shift through
the coil on 75m is clearly ~38 degrees.

I compiled the forward current magnitude and phase
into an EXCEL file and generated the graphics for
the self-resonant frequency of 7.96 MHz. That
file can be downloaded from:

http://www.w5dxp.com/coil505.xls
--
73, Cecil http://www.w5dxp.com