For wire antennas best is the wire called "Copperweld" or "DX Wire".
It is a hard steel core surrounded by thick copper, then insulation.
It gets the mechanical strength from steel, no stretching, and the copper
conductivity.
At warm places is even more important for temperature stretch.
73, Maximo - EA1DDO
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Richard
Smith
Sent: sábado, 27 de junio de 2020 16:50
To: towertalk@contesting.com
Subject: [TowerTalk] Choice of Antenna Wire for Multi-Element 80 Meter Yagi on
a Catenary
Hello TowerTalkers,
The team at PJ4K is planning to put up a 4-element wire yagi on 80 Meters with
Inverted-Vee type elements. It will be supported by a rope catenary between two
towers, at about 100' off the ground. In choosing the wire for the elements,
there is a trade-off between strength and weight of the wire. Currently, I'm
looking at Hard-Drawn copper wire as the wire choice, but I don't have
experience with it. Are there any concerns about the use of HD copper wire,
such as tendency for kinks, or other mechanical concerns?
I'm considering #14, #16, and #18 HD copper wire for the elements. I figured
out the approximate weights of wire for a 4 element 80 meter yagi:
4 elements of #14 copper wire weighs about 6.2 lbs Breaking strength is
213 lbs
4 elements of #16 copper wire weighs about 3.9 lbs Breaking strength is
135 lbs
4 elements of #18 copper wire weighs about 2.5 lbs Breaking strength is
85 lbs
I'm thinking that it's not just the dead weight of the wire to consider, but
also the fact that lighter wire will require less tension to pull out the ends
of the elements, to achieve about a 120 degree angle for the Inverted-Vee
elements.
I'm interested in suggestions, especially from those who have tried similar
antennas.
TNX and 73, Rich, N6KT
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