Pete Smith wrote:
>
> It does, but not a bunch.
>
> I quickly modeled a 40m yagi at 104 feet over average ground versus salt
> water. Forward gain went from 11.86 dBi (avg) at 18 degrees to 12.45 dBi
> (salt). Takeoff angle, interestingly, went up one degree for the better
> ground plane. Moving the antenna down 6 feet over salt water moved the
> takeoff angle up 1 more degree, from 19 to 20 degrees.
>
Just as an idle question.. I wonder if the gain change is due to a pattern
shape change (narrower main lobe), or due to a reduction in losses. The
average gain number would tell you, since it's integrated over all look
angles.
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