A proportional control radio remote control system which is used for construction machinery. It is installed on power shovels and many other types of construction machinery, and has won high feedback from customers. The system features five joysticks for proportional control so it is capable of supporting just about every kind of construction machine. The output signals from the receiver are RS-422 serial communication signals. Also available as an option is a control unit which enables hydraulic solenoid valves and other such parts to be driven directly. The specified low-power type of radio signals are used so the system is ready for immediate use with no license needing to be obtained in Japan.