I believe the antenna you are talking about looks like this. The top and
bottom ends of the dipole attach to the tower and the middle , where the
feed line attaches, is pulled out away from the tower some distance with a
rope to a stake in the ground or other attachment point. This supposedly
cancels vertical radiation. The feed line goes horizontally into the tower
and then down to the ground. One of the locals has a setup like this with 3
dipoles at 120 degrees. The feed line on the undriven 2 dipoles is such a
length that they act as reflectors and relays select the dipole to apply
power to so it is a switchable directional array. There is a 4 square
version in the ON4UN handboolk called the K8UR array.
73, Dan, N5AR
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Roger (K8RI)
Sent: Saturday, February 23, 2008 5:37 PM
Cc: TowerTalk
Subject: [TowerTalk] Bent Sloper
Oops, hit wrong button
A while back when discussing the half wave slopers it was mentioned
that bending the lower portion of the dipole back would give a lower
angle of radiation.
My question is where would the bend occur? would it be at the center
(feed point) with the lower half of the dipole being horizontal? IOW
the dipole would form a right triangle with the tower. The bottom half
would be horizontal with the top half being on about a 45 degree angle.
This would be the simplest, easiest, and take the least room.
This would require a bit of insulated line so the sloping part could
reach the tower. Depending on how far from the tower the horizontal
section ended (I'd prefer at least 10') then the extended portion for
the top would run around 40', plus a bit.
73
Roger (K8RI)
www.rogerhalstead.com
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