On Wed,12/2/2015 11:02 AM, Don Kirk wrote:
Therefore while I don't disagree that a vertical on 160 meters is a great
antenna especially for DX work, for working stations in close it sometimes
can be a disadvantage. Based on modeling it looks like a dipole only 15
feet off the ground on 160 meters would perform much better than my
vertical for signals arriving at very high angles (as an example).
You are misinterpreting the model data by looking at the shape of the
pattern rather than the relative strength of the pattern at angles of
interest. Example -- the so-called "take off angle" simply shows the
vertical angle where the signal is the strongest. FAR more important to
look at the field strength at various angles as the height is varied. I
did exactly that in an extensive modeling study comparing vertical and
horizontal antennas of various heights. While I concentrated my work on
80M and 40M, the results are directly applicable to 160M if heights in
feet are doubled from the 80M plots.
http://k9yc.com/VertOrHorizontal-Slides.pdf
Bottom line -- for 160M, we mere mortals simply can't get a horizontal
antenna too high for local QSOs, and higher is better, at least up to
200 ft.
73, Jim K9YC
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