Synchronisation method of TDM autonomous transmitting stations - in which cycle time is dependent only on number of transmitters within range as determined by stored information

At each transmitting station a control keyboard is connected to a parallel-to-serial convertor gated by the output of a control calculator operating on HF signals from the receiver. The calculator also opens an AND gate by which serial information from the keyboard is fed to the HF transmitter. A cycle time preselector is connected to the calculator ensuring that the individual transmission time slots of all transmitters within the range of reception are known and memorised. When a transmission is received from a source which was previously out of range, the transmission slot hitherto used is discarded and another is found whose position is memorised as a new individual one. The system is applicable, e.g. to railway telecontrol.