An Electronic System for the Phase Synchronization of Radio Transmitters

This paper describes an electronic system for synchronizing LW and MW broadcast transmitters operating in a phase synchronous network. In the introductory section, the stage of synchronous broadcasting is briefly discussed. Following sections present a block diagram of the system, point out some of its characteristics, and give basic differential equations and some other useful formulas charactizing the behavior of the system. System responses to a frequency step of the local oscillator and to a phase step of the received signal are given. Finally, some experiments with the system employed as an exciter of a MW transmitter being synchronized by the Czechoslovak and Swiss national frequency standards are described. The experiments also illustrate the effects of ionospheric phase anomalies and other limitations to the accuracy of the phase control.