The SC48RJ Tester provides rapid, positive testing for NL4 and NL8 type multiline speaker cables, RJ45 type data cables and XLR cables. The simple yet comprehensive design can diagnose opens, shorts, incorrect wiring or even customized wiring configurations in cables with up to eight conductors. The SC48 is powered by a single 9 Volt battery. Rotating the central switch applies voltage to the cable conductors one at a time. A SEND LED indicates the pin to which the voltage is being applied, and a RECEIVE LED indicates where it returns, clearly revealing, shorts, opens and cross-wires.