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Old May 17th 04, 06:30 PM
Dan Richardson
 
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On Mon, 17 May 2004 10:42:49 -0500, (Richard
Harrison) wrote:
[snip]
Power varies as the square of the voltage. One can see the difference in
the field strength is hardly worth the effort for an amateur to try to
increase the length of his antenna. It`s about a 3 dB gain from 1/4-wave
to 5/8 wave.

[snip]

The 3 dB gain figure is valid when mounted on theoretical perfect
ground. For a ground-plane elevated above real ground you'll find the
gain to be rarely greater than 1 dB.

Modeling 1/4 & 5/8-wave ground planes at 30 feet above ground (@ 24
MHz) as was described earlier NEC reports the following maximum gain:

1/4-wave 2.35 dB

5/8-wave 3.06 dB

73
Danny, K6MHE