Hi George,
> How do you straighten the wire?
By straighten, I assume that you mean taking out the curl.
I don't try to take the curl out. One fellow described his method of
taking out the curl in QST's "Hints & Kinks" quite a few years ago
which basically bent the wire in the opposite direction of the
curl by pulling it through a couple of nails or something like that.
(Try a search on the ARRL web site.) I would avoid using nails
because it may abrade the copper.
OTOH, if the wire is really KINKED the wire will most likely break at
some time
if the kink is straightened. The best advice I can offer in that case is
one
of prevention, i.e., not kinking it in the first place.
As always, its a good idea to wear some eye protection when
handling the springy wire.
> What sort of strain do you need to keep it tensioned over say a
> length of
> 200'?
Per an article in QST, Jan, 1966, page 57 the recommended tension
for #12 copper-clad steel at a span of 210 feet for #12 is 75 lbs,
for a sag of 5.1 feet.
> How do you treat the ends, i.e. say fixing to a strain insulator?
> Crimp or
> solder? I can't see you being able to twist this stuff much unlike
> copper.
Don't try to twist it!
You can use the same method that AT&T once used at their high seas
transmitting/receiving stations if you want a more "professional" method.
A wire end was slipped through the eye of an insulator, then the wire
was bent back toward the main run and formed into an "eye".
With the wires now parallel, they served (wrapped) the wires with a
winding of smaller soft copper wire, close wound. Then, they applied
flux and then *poured* molten solder over the connection.
Servings for 0.162 copper-steel (heavy-duty stuff!) were typically
about 1-1/2 inches long and they used 0.040 soft copper wire.
Their instructions were to never use a torch to solder the wire
because of the risk of annealing the wire. For practical ham use,
using one of those small butane torches would be OK, but heat
the wire just enough to flow the solder.
If the end needed to be connected to say, a transmission line,
an extra "tail:" wire was added and served and solder along with
the line wire. One could also use a longer end of the line wire,
and simply bend it out for a convenient connection after it had
been served.
If you use "pro" method, you may want to apply a gentle force with a
pair of pliers where the serving begins. You can avoid nicking the
copper
by using a few layers of tape on the jaws of the pliers.
Another method, far less permanent and perhaps less secure, is to use
the bronze or copper wire clamps you can find at a well stocked
hardware store. Those are great for temporary connections.
73,
Charlie, N0TT
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