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[email protected] · November 16th 14, 06:45 PM posted to rec.radio.amateur.antenna

Jeff Liebermann wrote:
On Sat, 15 Nov 2014 21:38:10 -0000, wrote:

The following shows the effect on elevation pattern for a 1/2 wave
dipole antenna over ground at various heights for perfect, very good,
average, and extremely ground.

The important value to note is the elevation angle for the main lobe.

Generally for DX an elevation angle at or below 30 degrees is desirable
and for NVIS an angle above 60 degrees.

This might help:
http://802.11junk.com/jeffl/antennas/horizontal-dipole/

Animated GIF of the horizontal 1/2 wave dipole over a "moderate"
ground at various heights:
http://802.11junk.com/jeffl/antennas/horizontal-dipole/horiz-dipole.gif
There's a big problem with the GIF. I couldn't convince 4NEC2 to fix
the scale on the gain plot. So, it changes in the middle of the
annimation. The outer ring is +5dBi for 0.1 to 0.3 wavelengths
height, and +10dBi for the others. I'll try to fix that later.

NEC deck for 4NEC2:
http://802.11junk.com/jeffl/antennas/horizontal-dipole/Dipole.nec

Yeah, graphs are better than tables of data any day.

--
Jim Pennino