Retirement is getting near and a QTH with a 4 square for 160m is not so far
away. A few questions have come up regarding construction of the array and
keeping it up. I plan to use 200 feet of Rohn 25G, run 4 nylon ropes off the
top and suspend 4 1/4 vertical wires from the ropes. The description is well
explained in ON4UN's book.
What is the best way to attach the bottom of the wires to the coaxlines?
What kind of base should I use at these points? And how do I prevent the
suspended wires from constantly bouncing and breaking loose. What type wire
would work best?
How do I attach the wires to the overhead ropes without the top part of the
wires breaking loose due to metal fatigue?
I intend to use a ground mounted radial system of 120 radials, 1/4
wavelength long from each of the four feedpoints. There is going to be a lot
of radials over lapping and I am wondering if I should bond the radials where
they over lap or just leave them as is? Do I loose anything by using a common
buss wire to attach the over lapping radials which would eliminate the
overlap? Will this method lenghten the rf return path and alter the
performance of the array?
In light of recent comments regarding Fresnel Zones I am also wondering if
I should extend all the radials to the limits of the lot. It is a 40 acre lot
and the array will be in the center so the shortest radial could be approx 500
feet long and others may reach out to approx 700 feet. Would I be improving
the reflection properties in the Fresnel Zone with these extended radials?
Joe AA6WG
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