Re: EZNEC Example of Short Vertical w/ Matching Coil

Roy Lewallen wrote:
But as some others have commented, it's much more common to take care of the capacitive reactance of a short whip with a series, rather than shunt, inductor.

Quoting the ARRL Antenna Book: "The input impedance of
short, high-Q coil-loaded antennas is quite low. For
example, an 8-foot antenna optimized for 3.9 MHz with
a coil Q of 300 and a ground loss resistance of two
ohms has a base input impedance of about 13 ohms."

It is common practice to adjust the feedpoint impedance
to about 13-j22 and install a base shunt inductive
reactance of ~+j30 to twist the feedpoint impedance
to a near perfect 50+j0 ohms.
--
73, Cecil http://www.w5dxp.com
.

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