On Sat, 2 Sep 2006 13:12:23 -0400, Gedas wrote:
>Hi Jim, I found your comments below interesting. Do you really
>see an advantage using solid wire over stranded for a given size?
Yes. A major disadvantage of stranded wire is that oxidation of each
individual strand degrades the overall electrical properties of the
wire over time. Obviously this is reduced by a good jacket, but
jackets abraid, and now you have oxidation. It's the same reason that
braid is bad news when exposed to conditions that cause oxidation. I
also find solid wire generally easier to work with and make strong
terminations at the ends.
Re: stretching when trees blow -- an ancient and accepted method of
dealing with that is with a pulley and a weight on one end rather
than a solidly tied rope. That said, I've never done that, and have
never lost an antenna in a tree. But now that all my antennas will be
wires in very tall trees, I'm going to adopt that practice when I get
my "permanent" wires up.
Another point. Copper DOES have a good amount of stretch before it
breaks if it isn't already hard drawn. This may be why so many of us
have such good luck with wires in trees.
In my limited experience, wire antennas come down because something
breaks at a weak point when stressed. Learning how to avoid these
weak points, and to minimize the stresses, is the key to making them
stay up. And every little bit helps -- beefier solid wire with some
stretch, the pulley/weight, avoiding solder at points that will be
flexed, solid, smooth tie-offs, etc.
Jim Brown K9YC
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