I've used 3 runs of half-inch CATVC hardline, buried for 200 feet, as
control cable (FREE is about as cheap as it gets). Center conductor and
shield gave me 6 conductors total. The starting capacitor always goes at the
tower, so that eliminates the need for two conductors (terminals 4 and 8 on
a T2X or Ham-type rotor).
Last time I bought new rotor cable was 1978. It was also the first time. 100
feet of it, still going strong
.
In addition to using hardline, I've picked up various spools of jacketed
multi-conductor cable at hamfests, yard sales and a local recycling yard
that sells it by the pound, more or less, with much dickering allowed. It's
always a fraction of what new 8-conductor cable would cost. Some of it has
small conductors -- perhaps Number 22 or 24 -- but many of them; 20 or 30.
Probably from telephone or computer applications. I just use several
conductors in parallel so there's enough current-carrying capacity.
You can use old coax too or just about any kind of wire.
Another way to save is to let several rotors share one rotor cable. I do
this by having one conductor dedicated as a control line. Using plus and
minus voltages on the control line I can get three relay positions (plus,
minus and zero voltage). The relays switch the 6 rotor conductors among the
three rotators. Works fine as long as you don't need a constant direction
indication. If you do, you could still save on cable by using relays to just
switch the brake and motor lines.
73/Jon AA1K
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