[GreenKeys] What type of wire for loop?

[Jeffrey Angus]

You guys are WAY over thinking this.
<https://www.cirris.com/learning-center/calculators/133-wire-resistance-calculator-table?>
52800' of #24 copper wire is 1355.376 Ohms. That's?? 5 miles
of copper pair.
If you up the wire size to #18, you can go as far as 20 miles
of copper pair.

There's a reason they use 120 vdc with a 2 K series resistor.
It approximates a current source, and allows for a clean
square wave into an inductive load.

The loop doesn't give a damn where the series resistance is.
It can be a 2K wire wound resistor in the supply, or it can be
split with 1350 ohms in the loop wiring and 650 Ohms in
the supply.

If you run iron wire, The total loop length for a given AWG
size is going to be shorter. Actually, for the same given AWG,
it will 5.77 times more ohms/foot.

So for example #18 iron wire is good for about 3.4 miles
instead of the 20 miles for copper.

Secondly, to twist or not.
Standard practice is to put a cross over every nnn feet. I'm
thinking 1000-2000 ft. This is done to prevent cross talk
between adjacent pairs.

Transmission line theory works just as well at 23 Hz as it does
at 3 GHz.




-- 
"I am a river to my people."
Jeff-1.0
WA6FWI
www.foxsmercantile.com