[TowerTalk] 160m Slopers

[Jim Thomson]

Date: Wed, 25 Jan 2017 22:23:01 -0500
From: <john at kk9a.com>
To: <towertalk at 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