There is a great wire out there for both antennas and radials that few folks
seem to
know about ... it is the telco aerial wire running from pole to house ...
made with two
+ACM-18 gage electroplated copper wires (... common term Copperweld .. which is
a
brand/trade name however) inside pvc insulation and the whole thing looks
like
one hefty zip cord. Something like 300 lbs breaking strength or so ....
Also out there is a slitter for this wire, a razor blade in a holder that
will allow you
to slit the zip cord wire in two ... resulting in two separate conductors
fully insulated in pvc.
The springy wire inside is tamed and working with the singles is a dream ...
I have used
this for antenna wire for years with great success .. yet it does not meet
the NEC call for
+ACM-14/+ACM-12 hard drawn or electroplated copper on steel/iron. Copper
thickness is on
the order of 3 mils (0.003 inches) and is more than adequate for modest
power at
any RF HF hamband frequency. Many skins deep at HF ham band freqs.
DO NOT use this wire as a feedline or a transmission line, it's RF loss is
HUGE
in that the PVC insulation has a very high dielectric constant and further
degrades
in the presence of rain or water which further increases losses ... The line
performs
OK at voice frequencies but anything above that is questionable wisdom. I
know this
as fact since I have measured thousands of feet of it at all frequencies
many many times
over the years in the telco wire/cable manufacturing environment ...
Slit the wire instead and use the singles .... to make
antennas/bevereges/ground radials +ACY-
elevated radials. Putting these singles insulated with PVC in the ground
solves just
about all your concerns .. The PVC insulation responds to moisture and the
RF
couple of the wire to earth is extremely high+ACE- Corrosion is basically non
exisitent,
basically because the adhesion of the pvc to the wire is so tight/complete
that no
significant air or water can track along the wire and give rise to
significant corrosion affecting
RF current flow ... I have dug up this stuff in Georgia soils after 15 years
and it
is as good as new+ACE-
There is a procedure for removing the insulation with a half sharp/dull
knife, and after
it has been removed soldering is easily accomplished .. but one should then
paint
the joint to drastically reduce the rate of rust thru ... water permeates
the cracks in the
copper skin and reaches the iron core beneath and the wire rusts open ...
and breaks.
And I have had one such failure in 25 years+ACE- Unexposed wire withstands
significant
tensions for decades as well as survival in the buried environment. I have
used the
BARE wire for antenna wire under low tension and have never had a failure
in over
30 years ...
Were do you get this stuff? Your local telco can advise you ... Graybar
and similar companies
carry this stuff .. it usually comes in packages of 1000 to 2000 feet
(double that for total
single wire count ... after slitting) ... Called aerial drop, F-drop, ADP,
etc names by
the various vendors. The local lineman has some loose ends as well ... and
you
can find the supply house/manufacturer ... manufacturers have lots of scrap
that goes in the
trash .. the copper is not economcially recoverable ... Wherever you find
it, the price
per foot is probably way below other wires out there ... Supply reels of
this wire typically come
in 500K feet sizes and the bottom end scrap that is left when on-the-fly
change
overs occur is enuff to last the ham community a bunch of years+ACE- Dunno if
Press the
WIreman handles such or not ... probably not be my guess.
If you would like a sample, let me know and I'll send you some ...
My lifetime supply is now down to about 750,000 feet ... so I can
still spare a few feet ...
... de Dave (a/k/a +ACI-W+ACI-) +AEA- nc7w ...Brigham Utah
P.S. I also keep a good roll in the car trunk to pull myself or someone
else
out of the ditch, etc ...
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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