Additionally it can use signal wire to communicate up to 500 meters.

You're always going to need to run power to a TV location anyway so you can run a signal wire at the same time.

They knew when we crossed the signal wire.

Communications were lost but the break in the signal wire was found and repaired.

"There is the signal wire - we laid it last night."

These signal wires carry two copies of the same signal, but with opposite polarity.

The signal wire was a separate device that had been placed there.

He figured that the signal wire had short-circuited and decided to investigate.

Jack agreed and they set off down the track side, treading carefully in case they tripped over signal wire.

The signal wire had been cut by now, and communications with the battalions were shaky.