Good morning.
Appreciate a chance to test this e-mail system after having a catastrophic
software crash about 2 weeks ago. Am really behind and having to work off-line
to retrieve the files.
Anyway.............
My preference for antenna wire is Alum-O-Weld. I noticed many replies
suggesting
copperweld and Alum-O-Weld is essentially the same, but with a cladding of
aluminum instead of copper. According to the manufacturer, the aluminum
cladding
will even self-heal to some degree in the case of a nick in the cladding
surface. On copperweld, the core will rust if the nick is through the cladding.
It is lighter weight than copperweld.
"Cladding" is an important term, as distinguished from "plated." Cladding is at
least 10% of the overall diameter, whereas plated wire might not be thick
enough
and the current can penetrate into the very lossy steel (ferrous) core. We have
run tests in this area and Moxon has references in his book about ferrous
material losses, including this one on page page 248 ("Open-wire Line") of the
first edition, "In one case an observed loss of about 6dB on 100yd (91m) of
line
was traced to surplus 'copper' wire which turned out to be not copper but
copper-plated steel." Probably didn't have any ice build-up on this feed system!
We use #12 Alum-O-Weld, which is the smallest available and have tested with
#10
and #8. The largest customers for this wire are the power companies. The
Alum-O-Weld is lighter and apparently lasts longer than their copper lines.
Alum-O-Weld is made in much larger sizes, plus being stranded. A single piece
of
#12 has a tensile strength of 1,100 pounds. Complete aluminum hardware is also
available for using Alum-O-Weld for guy systems.
We have also built some wire Yagis using Alum-O-Weld (i.e. PJ1B 3el 80 mtr. The
electrical connections need special attention to be sure there is always good
contact.
Have a great day,
Tom Schiller, N6BT
President, Force 12, Inc.
P.O. Box 1349 Paso RObles, CA 93447
Phone: 805.227.1680 FAX 805.227.1684
Web Site: http://www.QTH.com/force12
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