Insulated wire or
Antenna list, May 2000
?: I almost always see wire antennas made from solid, non-insulated
wire. Is there a reason not to use stranded, insulated wire?
n4xy: Strength and stretch are the negatives, Richard.
Being stranded, and having insulation, has negligible impact on
actual HF/VHF performance.
The insulation does help keep the copper 'fresh, but I have never
found that to matter either, personally.
Use what you have, or can get.
If you get an antenna up high enough that strength matters,
then you really need to consider copperweld. I don't enjoy
replacing broken antennas, and have a lot of 'whip' in my trees,
so I pretty much have to use strong (e.g. copperweld) wire.
Dave, nr1dx: The only real draw back that I can see is that
insulated wire is heavier per unit length. As such it does put more
strain on certain components in the support structure as well as
the wire itself.
I have used insulated wire for dipoles, inverted L's , and even
Beverages for years with relatively good success. Of late I have
changed to the bare copperweld and my antennas tend to survive in
wind, ice and snow storms better.
You are correct in that insulated wires antennas are shorter by
about 1.5 to 2% at resonance than their bare counterparts.
Carl, km1h: I've had minimal problem with insulated stranded
( not house wire), usually #10 or 12 tinned and 19 strands or more.
Stretch has been insignificant.
For serious use between the tops of pine trees I use #12 solid and
insulated CopperWeld, also known as rural telephone line wire. The
black insulation is known as APS...Anti Percipitation Static and
it does a good job in rain or snow. Even then I use a pair of heavy
duty door springs to act as shock absorbers.
The worst stuff Ive used for antenna wire is stranded CopperWeld.
A few years in NE acid rain and it rots and unravels.
Jay, w6cj: For temporary, or hidden, HF wire antennas I prefer
thin, insulated wire.
It works fine for tuner-fed balanced or endfed antennas and will
work on plain-old dipoles with coax feed. The slippery insulation
(teflon) is best for throwing over or through trees.
It won't snag.
John Matz, kb9ii: Two of my wire antennas are made from insulated
solid house wire. A few things I have noted:
Stretch seems negligible, the insulation pulls it low in freq, it's
a little heavier, strength is adequate in inverted vee configuration,
the insulation can't take the sun and rain and snow around Chicago
very well, but it's been up for four years and seems ok.
I used black #14 for minimum visibility.
Carl, km1h: Several asked where to get rural telephone wire
that is #12 insulated Copperweld
Since I'm basically lazy, here is a one short reply.
I've bought mine in 1000' to 5000' lots; they will put up on 500'
rolls at no charge which makes it nice for group buys.
I purchased the extra high conductivity version....more copper I
I've used it here for Beverages and regular wire antennas that needed
strength and percipitation noise reduction.
You can get a catalog from:
Clifford Wire, 1-800-451-4381, in Vermount.
Web site: http://www.cliffordvt.com/
David Robbins, k1ttt: Just don't ask for Copperweld when
you call them, they'll have no idea what you are talking about.
What you are looking for from them is "Line Wire, Single Conductor
IMSA spec 28-3". They describe the conductor as 'copperweld' or
'copperply' and the insulation as black hdpe. They have 12ga and
10ga in the catalog I have.
The standard reel length is 5000', but they will cut shorter lengths.
I have been using this stuff for years for beverages, inverted V's,
and verticals. it holds up to everything, including ice, trees falling
on it, bears flossing with it, and moose running into it.