The Discrete Address Beacon System (DABS) Calibration Performance Monitor Equipment (CPME) is a special DABS transponder designed for installation at a fixed site visible to one or more DABS beacon sensors. The CPME is required for DABS sensor monopulse accuracy tests and for calibration of the sensor off-boresite azimuth look-up table. In addition, the CPME provides tests for DABS link integrity, by storing an uplink message and parroting it back upon command from the sensor. This document contains all information necessary to obtain a general understanding of the CPME system and its operation. Detailed information necessary for repair of the equipment is not contained in this document, but is supplied with each CPME system.