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Date: Wed, 28 Jun 2000 11:24:41 +0100
To: rsgb_lf_group@blacksheep.org
From: "Brian Rogerson" <brian@esoterica.pt>
Subject: Re: LF: Wire, for LF Antennas
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Aluminium?

Much lighter so you can use larger diameters.  I use it extensively now,
without
problem to date but can only claim a 40m span folded dipole with 2.5mm
diameter wire.

Brian, CT1DRP

At 06:06 28/06/00 -0400, you wrote:
>Greetings:
>
>Preparations continue for TransAtlantic II, the test transmissions from here
>in Eastern Ontario on 137.710 kHz are now heard widely in the USA and
>Canada.
>
>Moving forward through the lists of things and issues to be worked on, the
>subject of WIRE for LF antennas comes up.  The objective of this email is to
>have a discussion with active LF amateurs that will ensure for me at the end
>of the day that the best alternatives have been discovered and considered
>for use here.
>
>The current antenna here for the test transmissions is made from what we
>here call common antenna wire, 7 strands of semi hard copper wire, commonly
>known as 7/24.  For LF the type of wire is marginal, when used for long
>spans it stretches and anneals, becomes eventually very brittle and fails.
>A lousy wire solution for long spans associated with LF antennas.  The LF
>test antenna here is far from optimum because I simply do not dare to
>stretch the wire harder with the rope that pulls the antenna away from the
>supporting tower.
>
>The alternative selections available here are very limited.  There is a
>reasonable quantity of semi hard drawn solid copper wire #12, commonly used
>by the Broadcast Station industry.  I use this for MF/HF antennas but it is
>also subject to annealing and stretching.
>
>We have available an insulated wire known variously as "FlexWeave", similar
>to Litz wire but without the shellac to hold the wire together.  This is
>around 75 and 150 strands in the two sizes that are usually available.  The
>issue here again is strength, 150 Meter spans do not last very long.
>
>The last is the good old copper clad steel wire, not much copper any more
>but usually pretty good for long spans.  Sources of this product are
>limited, a good source here in Canada would be a help.
>
>What are the other alternatives that you are using in your setup?  Why are
>they good?  What is the usual cost in your area?  If you were looking at
>spans of up to 300 Meters what would you use for an antenna wire?
>
>Not a glorious subject, but one which is important to the LF community.
>Your comments are solicited.
>
>Larry
>VA3LK
>
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