Ola Josep,
> Have my 25m Top Loaded Vertical around 1/4wvl away from my other 16m high
> self-supported tower, with a Cuschraft 4el yagi on top. The line-of-fire
is
> beaming to about 30 degrees.
I have a 78 meter tower (on insulator) 165 meters (one wavelength) away
from my verticals, and it makes a very noticeable change in pattern of my
verticals. If I ground it or float it the pattern of my vertical still
changes greatly. It still has a measurable but small effect even when
detuned with a series inductor to ground.
It is a common problem for 160 antennas to couple to everything around
them, because electrically even long distances are close in terms of
wavelength. Maybe you can drive both towers and have a nice beam? I did
that at my last location by phasing a 100 foot high 40 meter dipole (with
the feedline tied together like a T antenna) against a shunt fed tower 100
feet away. I got good F/B (over 20 dB) and a few dB gain. Elements do not
have to be symmetrical to be phased.
73 Tom
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