If you don't have a multimeter.
Get a battery (the small rectangular ones with the + and - at the top) and connect the centre core of the coaxial cable to one end and the copper braid to the other.
Use a torch bulb at the other end and the wire that lights the bulb is identified.
But I'm sure the S*y engineer will do it in seconds for you.
__________________  Only he who does nothing, does nothing wrong. |