Utilizing an advanced form of Spread Spectrum Time Domain Reflectometry that allows its use over energized cables, Snap Shot TDR accurately detects, locates and identifies fault conditions such as opens, shorts, and arc faults on energized cable of all types up to 3,000 feet in length. A large, backlit LCD display clearly shows lengths in both feet and/or meters with an accuracy of better than one percent for pinpointing any fault or condition. Dual internal memory allows users to store cable parameters for easy reference, while a built in tone generator with multiple tone capabilities trace found faults.