In the past I have used alligator clips and clipped the black (-) wire to ground and the red (+) wire to the end of the wire I was tracing (multimeter one). With multimeter two in hand I would go to the location (to far to ohm check with one mutimeter and lead) and start checking for the other end of the wire by grounding the black (-) and touching the other wires one by one with the positive red lead. When the wire was found the multimter would produce an audible tone. In the past the multimeters were the same brand and model number. I have two different meters this time. and no audible. Do I have to have the same make and model numbers?