Congratulations on your purchase of the Dranetz 656 Disturbance Waveform Analyzer. We are confident you will be delighted with the unit’s unique analyzing capabilities, as well as its ability to download events to a disk for permanent storage and later recall. The 656 is a powerful, self-contained, portable instrument that captures, records, analyzes, and displays AC and DC power line disturbances on four power acquisition channels. With available options installed, the 656 also monitors radiated and conducted RF (radio frequency) energy levels and environmental temperature and humidity changes using its Sensor (transducer) channels. The 656A monitors current as well as voltage. The 656 is designed for easy operation. All selections and entries are prompted by the CRT, and the Operator is never more than a keystroke away from a "Help" screen. This lets you run the 656 without having to continually refer to this manual for instructions.