Abstract: The inventor discloses an ultra narrow band relatively ultra stable radio apparatus for communicting paging or control signals from a central transmitter to a multiplicity of remotely located receivers, which receivers may be carried on the person of individuals or may be fixed to other devices which they control, such as city traffic control lights, programmable signs, machines, or the like, wherein the central transmitting device and the remote receiving device are both phase locked to a local broadcast station RF carrier so as to provide a means to precisely synchronize the transmitting device with the receiving device and thereby achieve very high signal-to-noise ratio transmissions. The apparatus is capable of transmitting a digital identification code or a digital message and the receiving devices may output a simple on-off signal indicating the presence of a call, or digital message may be output to control an apparatus attached to said receiver.