I'm looking at the exact same scenario Bill.
I have been poking around using AutoEZ (a front end for EZNEC) where the guy
has cooked up a comprehensive model for the 4-square inclusive of a hybrid
combiner. Once you get the model figured out the program provides HUGE HUGE
flexibility in whatever variables you want to kick the virtual tires on
without having to go out and do the considerable leg work to try out an
idea. Take a look here if you are interested in seeing what modeling will
do for you.
http://ac6la.com/aecollection8.html
From my fiddling around with AutoEZ, there is a nice improvement in the dump
power related bandwidth using any sort of fatter element. I did not look at
any spacing as small as yours (mine was 1') because I could not have
confidence in being able to keep the wires from twisting here in the local
frequent winds. A pair of wires separated into a rectangle shape spaced
1/2/3/4' were all about the same in producing the desired broad-banding. So
I would say in theory going this route pays off.
The hassle is in cooking up a method to keep the wires from twisting around
each other. My mechanical idea is to bring them up to a point at the top
where the rope support is, and have them fat near the ground with the
thought that you want the "fat" part of the element near the current max.
That triangle shape makes construction simple as well.
Good luck
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-----Original Message-----
From: Bill via TowerTalk
Sent: Friday, November 10, 2017 7:51 PM
To: towertalk@contesting.com
Subject: [TowerTalk] 4 square advice
I'm starting construction of my wire 4 square for 80 meters.
I know the bigger the diameter is (like having Rohn 25 tower for the
radiator) the better the bandwidth.
I'm using #12 insulated wire, but in an effort to enhance bandwidth I'm
planning using two wires joined at the top and at the feedpoint for each
element. To space them I'm using some old KLM diamond shaped spacers every
five feet or so to keep the two wires approximately 5 or 6 inches from each
other...running the wires parallel to each other.
Any thoughts as to how helpful this will be in increasing bandwidth? I have
about 45 of these spacers and they're just gathering dust, and they are
lightweight, UV resistant and free. Also, any thoughts as to how this might
affect the impedance etc.?
Bill K4XS/KH7XS
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