TopBand: Elevated GP vs. Vertical Antennas

[Eric Gustafson Courtesy Account]

>Date: Wed, 18 Mar 1998 18:53:18 -0700
>From: Eric Gustafson Courtesy Account <n7cl@sparx.mmsi.com>

Snip...

>As a practical matter, you really don't need to go all the way to
>10 wavelengths.  Three wavelengths would get your TOA down to the
>5 degree region (I believe, I'll check that one out and get back
>to you.) with the 3dB point much lower than that.
>

I was wrong. the TOA is only going to come down into the 10 to 15
degree area (over 5 mS, e=13 ground) with 630 #12 3 wavelength
long radials which are laying on the earths surface.  The 3 dB
points of the main lobe should be at approximately 3 and 43
degrees.

What IS true is that you will have gotten all but 0.5 dB or so of
the possible improvement in the strength in the pattern at angles
above 10 degrees.

73, Eric  N7CL

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