"never argue with an idiot. He'll drag you down to his level and beat you with experience".

About 38 years ago, I set up a long line over 28 cable miles. It wasn't easy back in those days, because I was not able to just order an amplifier, so I used a pair of loop extenders wired back to back in each of my offices.

You should have heard the cussing when they finally pulled the cross connects :-) The loop extender uses about 140 volts to ground to signal LOL