The objective of this investigation was to develop and field test a prototype synthetic pulse radar system for in-seam hazard detection. The system consists of three major components: (1) the control unit, (2) the transmitter and antenna, and (3) the receiver and antenna. The system employs a hetrodyne receiver and two synthetizers that are phase-locked together with a 1-mhz offset. A fiber optic link is used to help eliminate direct feedthrough. The transmitted frequencies are in the 20- to 160-mhz range, with a minimum frequency spacing of 100 khz, providing a time window of 10,000 ns. The system is packaged with self-contained batteries for in-mine use. A secondary processor was designed and breadboarded to display data in the field. This processor, or any other mini- computer, can access the system using standard serial or parallel interfaces. The work was based upon the results of a previous Bureau of Mines contract, "coal mine hazard detection using synthetic pulse radar," OFR 79-81.