Abstract: A system enabling the frequency, and if desired, phase control of an oscillator which generates a standard signal useful as a carrier which is modulated by modulation signals. A multiplicity of such oscillators and associated transmitters may be used in a simulcast transmission system. The transmissions originate from a station which may be remote from the transmitters. The station has a system controller and the transmitters have transmitter controllers. For frequency control a reference signal generated in the system controller is transmitted over the same link and band width (e.g. the voice band width) with the voice modulating signals to the transmitter controllers of all of the transmitters.