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February 23rd 04, 05:10 PM

Dan Richardson

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On Mon, 23 Feb 2004 08:54:50 -0600 (CST),
(Richard Harrison) wrote:

A versatile antenna tuner can insert either inductive or capacitive
reactance in series with an antenna to correct its power factor (tune it
to resonance) so it can accept maximum excitation.

I believe you are confusing matching with antenna operation (gain and
efficiency). Using a simple dipole for example, you can calculate both
gain and efficiency using NEC. Doing that I have modeled a dipole at
3/8, 1/2 and 5/8-wavelengths (80-meter band). The antenna was modeled
using #14 copper wire in free space. Here is what NEC reported:

Wavelength Gain(DBi) Efficiency

3/8 1.8 96.36%
1/2 (resonate) 2.02 97.22%
5/8 2.29 97.72%

Clearly you should be able to see that only advantage is that the
longer antenna has greater the gain and efficiency. The fact antenna
is resonance or not is not the determining factor.

73
Danny, K6MHE

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