scope:

The Voice Frequency Control System specified herein will be a part of a composite system which operates remotely located transmitters and receivers for two air/ground channels over a single telephone circuit. The VF Control System, supplemented with local transmitter controls, shall accomplish the switching, and an associated VF Signaling System, (not a part of the equipment specified herein), shall provide the required tone signaling equipment. The control terminal will be in an Air Traffic Control Center and the controlled transmitters and receivers will be at a remote site called a Remote Controlled Air/Ground Station (RCAG).