You should come to Michigan. Salt on the roads is way of life and not
just in the winter. Salt/brine is readily and easily obtainable, plus
it's cheap!. When I was young (a very long time ago), most of the roads
were gravel. After a few months of dry summer weather, the sand and
stone were pulverized to form that created a thick, choking dust cloud
every time a car went by. Brine trucks, spraying the roads were a
common site. This not only eliminated the dust for a few months, but
turned those dirt roads into a concrete like surface with some big chuck
holes to boot. Usually by mid summer they (the county) would dig up the
surface, spray with brine again and grade to a smooth surface. As there
were seldom more than a couple houses per mile, the trucks would spray a
section starting and ending about a 100 yards each direction from the
homes. To give them credit, there is little brine spraying in the
summer. OTOH there is not only salt, but Calcium Chloride use as it
works in the colder winter temps. Sodium Chloride, ceases to function on
cold days and nites. There was no Aluminum in cars back then.
Telephone lines were just a pair of Aluminum clad, steel wires, about
#10, or slightly larger, mounted on those antique green insulators.
Switching was strictly manual with "Operators" operating large "patch
panels". For some time my antennas were made of thole Al clad steel
wires. Where ever one "hit the dirt", it would show rust within a
couple of weeks.
Most of us thought they worked quite well.. Few had real Cu wire. Al
wire? Copper Weld? What were they? Yagi antennas were a rarity. Gain
antennas were Rhombics, V-beams, Bobtail curtains, or just plain long
wire. Nearly all antennas were home built. Aluminum tubing of strong
alloys was almost unheard of. 10 to 20 years later we were seeing
simple phased vertical arrays along with the introduction of the Yagi
antenna.. As antennas were usually simple and power was relatively low,
IIRC an outstanding signal might get a visit to see just how much power
you were running. Back then the FCC had teeth, not the politically, and
selectively applied like at present, nor did they cheer-lead industries
with agendas that would have run counter to the existing rules.
Today we have commissioners retire and almost immediately go to work for
companies like LightSquared. Do a search on them and their political
involvement.
73
Roger (K8RI)
On 9/18/2015 11:49 AM, w1eqo@shaysnet.com wrote:
I have used many types of Copperweld in my consulting business. A couple of
times I have called their engineering staff about products.
One time I asked about the aluminum on steel product, which I believe was
called "aluminumweld." (Not to be confused with aluminum arc-welding wire)
I was told if the wire was used on ground or buried I would have dust in a
year or two.
This has to do with dissimilar metal action in the presence of an
electrolyte.
Here, in New England that electrolyte can be supplied by acid rain,
fertilizer, salt air (near the coast), or salt from plowing snow. Locally
the City Fathers have decided that plowing with salt during smaller snow
storms is less expensive, for them, then using an actual plow.
Here the action of aluminum can often be seen on pick-up trucks and vans
where an aluminum "running board," or step has been installed. After a few
years, fair sized spots of rust develop where the step is attached. A few
more years results in holes.
Wikipedia has a nice page that discusses dissimilar metals. Essentially the
two metals and electrolyte makes a battery, that has a short-circuit. The
"trick" to using dissimilar metals is to pick two that are close on the
voltage scale.
Like copper and steel.
The other thing to look at is the thickness of the copper on copperweld.
The company uses a conductivity scale to describe thickness, measured at 60
Hz. Very different at 1.8 MHz.
In the past I recall they had a different scale where I calculated that
their 30% conductivity for something like #10 wire was adequate. But memory
slips with age.
I do remember you will need to be careful with "copper coated" wire. A very
thin plating does you no good at all, you are using steel with it's poor
conductivity. Around 3% of copper, if memory serves me.
Pure aluminum wore is just fine. You should use a larger size than copper
for two reasons: strength, and conductivity. Aluminum is roughly 50% that
of copper.
I would keep aluminum from the ground, tho.
Jim, W1EQO
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Roger (K8RI)
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