At 08:54 AM 10/13/2005, K4SAV wrote:
>The gain decrease is because of wire surface area. Conductivity of
>aluminum is actually less than zinc, but the surface area of a #17 wire
>is much smaller than the surface area of a 1/2 inch diameter cable.
>
>The pattern formed by a long wire is very complex. There are large
>numbers of lobes and nulls, both in the azimuth and elevation
>directions. Most of these are very narrow. Because of this any small
>phase change in the current, causes large changes in the pattern.
To that end, you might be best served by "averaging" the pattern over some
reasonable intervals (say, 5x5 degree squares or something). They do
something similar when trying to describe in a few numbers the sidelobe
performance of high gain antennas.. you look at things like peak sidelobe
or integrated sidelobe or rms sidelobe, depending on what's most evil for
your application.
Jim, W6RMK
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