Hi Dave -
If you have not yet, you should check out ON4UN's Low Band DX Handbook.
John covers a number of lowband "three squares".
About 40 years ago I started out with three each halfwave slopers - every
120 degrees - hung from a 100 foot tower. Then, between each dipole I ran a
140 foot reflector wire. It really worked quite well. Next, I folded the
bottom half of the dipole back to, but not connected to, the base of the
tower. This causes the horizontal component of the radiation to be canceled
and leaves a nice low angle (18 degree) vetrtical radiation pattern. By
using the proper length feedline, when slecting one of the three "bent
dipoles" and leaving the other two open circuit you wind up with a
directional array with one driven and two refelector elements with 3 or4 dbd
of gain, with about 120 degree azimuth coverage and 10-15 db F/B. Not quite
a good as a good as a conventional four square, but very effective and
requires no radials. It could also be configured with four dipoles to give
a little better more gain and better F/B but the law of diminishing returns
is in effect. I also now use the three former 140 foot 80 meter reflector
wires as 160 meter quarterwave slopers. A relay box at the top of the tower
selects any one of the three slopers. Although there is only 3 or 4 db "F/B"
between the slopers, picking up an additional 3 or 4 db at times can be very
helpful - wouldn't you rather have 1.5 Kw instead of 750 watts.
Good luck with what ever you decide to go with.
Gene / W2LU
----- Original Message -----
From: "dave arruzza" <w1ctn@yahoo.com>
To: <towertalk@contesting.com>
Sent: Tuesday, October 25, 2011 4:50 PM
Subject: [TowerTalk] Triangle vertical array
To all...
I would appreciate any info the group has on triangle vertical arrays for 40
and/or 80 meters.
The 4 square project I had planned always puts 1 vertical to close to the
house. A triangle array would overcome that problem.
I need another project to keep me off the streets !
73
Dave
W1CTN
Radio Ansonia
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