Date: Wed, 25 Jan 2017 22:23:01 -0500
From: <john@kk9a.com>
To: <towertalk@contesting.com>
Subject: Re: [TowerTalk] 160m Slopers
This is a half sloper so the tower is a radiator. Whether it works well or
not depends on the tower and other mounted antennas. I imagine that this is
addressed in the Antenna Handbook. You would likely have better results
shunt feeding the tower or using a wire vertical.
John KK9A
## problem with shunt feeding any tower is.... then you require radials..which
is a pita.
Thats the beauty of the .25 wave sloper. Its an upside down GP, with the
portion of tower
that is above the feedpoint, and the yagis on top of the tower, the cold side.
The .25 wave
sloping wire is the hot side. Then the feedpoint is elevated well above the
ground.
## One thing that a buddy found out long ago, when a 2 nd .25 wave sloper was
installed, in the
opposite direction, and a remote switch box used..., that also grounded the
center conductor
of all un-used ants.... both .25 wave slopers ceased to work. Either one will
work provided the
un-used one was not grounded via a remote switch box.
## But if both are fed at the same time.....and spaced not too far apart, and
also stagger tuned, they should
both work, and cover a huge chunk of the 160m band. What else that works is
using bigger gauge wire, like
10 ga... or 8 ga. Broadens the swr curve quite a bit.
## LL .25 wave slopers also work, as does coil loaded .25 wave slopers, with
any coil close to the feedpoint..
like 1- 20 feet from the feedpoint.
Jim VE7RF
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