The first general use of radio control systems in models started in the early 1950s with single-channel self-built equipment; commercial equipment came later. The advent of greatly reduced the battery requirements, since the current requirements at low voltage were greatly reduced and the high voltage battery was eliminated. In both tube and early transistor sets the model's control surfaces were usually operated by an electromagnetic controlling the stored energy in a rubber-band loop, allowing simple on/off rudder control (right, left, and neutral) and sometimes other functions such as motor speed.
These systems were widely used until the 1960s, when the increasing use of systems greatly simplified radio control. The electromechanical systems using were replaced by similar electronic ones, and the continued miniaturization of electronics allowed more signals, referred to as , to be packed into the same package. While early control systems might have two or three channels using , modern systems include 20 or more using .
Most WWVB radio controlled clocks work great, as evidenced by the hundreds of thousands of units that have been sold throughout the United States. However, if your radio clock or receiver isn't working, we suggest: