Design and applications of a versatile multiplexed telemetry and power system for coax cables

By using frequency multiplexing techniques, a coax cable can be used to simultaneously receive sensor data and video signals from a subsea instrument package and transmit control signals and power for motors, lights, etc. Although this could be more easily accomplished using a multiconductor or fiber optic cable, the 0.68" armored coax cable is still the most common cable found in use on most oceanographic vessels. The techniques described in this paper have been used by others, however, this system makes extensive use of standard industrial controllers and sensors to produce a relatively low cost, versatile system that can be designed and built in a relatively short time period