T A RUSSELL, N4KG wrote:
>
> The answer to why verticals perform poorly on the high bands lies in
> the pseudo-Brewster angle effect where low angles are sucked out
> unless there is EXTREMELY good ground conductivity in the antenna
> foreground, presumably for more than a wavelength...
> Below about 10 to 15 degrees, there is considerable low angle loss
> over average earth on the higher bands.
Part of it is that; plus a poor ground system common to high band
vertical users. I had a 13 element parasitic vertical array (5 direc-
tors; 7 reflectors arranged in a parabolic fashion) for 20 meters
fixed on Europe for a couple of months at a past QTH. It was competi-
tive towards Europe with the best Yagi's on the band. I took it down
after a relatively short time since it was built as a prototype for
a low band antenna (no room for a low band version then) and it was
time to install the fall's low band antennas. The ground conductivity
was excellent there and I had a good ground system installed.
It obviously wasn't a very versatile antenna and I would only recommend
something similar for someone with height restrictions, a willingness
to put in much design and tuning time, and an unnatural love of mowing
around objects (each of my 13 elements had 3 guy anchor points, plus
its base).
73, Bill K0HA
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