Abstract: A control system for regulating the speed of a truck-mounted material conveyor includes a direct current drive motor and a truck-driven shunt generator for providing power to the motor. A control circuit has a reference input representing desired delivery rates in material weight per unit of distance and a truck speed input. A multiplier circuit converts the inputs to a delivery rate in terms of material weight per unit of time at the current truck road speed. Generator and conveyor speed feedback loops are provided to maintain a desired conveyor speed despite variations in truck engine speed or slippage at the conveyor.