Abstract: A switch machine operates a track switch under radio control via a switch controller. The switch controller may be given an identifying address unique to it which distinguishes the switch machine from other switch machines in the railway territory. In addressing or programming the switch machine, a portable terminal is used. The controller is enabled by a manually actuable switch to accept identifying addresses which is stored in electrically erasable programmable read-only memory (EEPROM). Whenever a message is received over the radio link, the identifying address is read out of memory. In order that the identifying address is vital (fail-safe) and to guard against any errors which change the identifying address and which can cause the controller to effectuate operation of the track switch in front of an oncoming train or when the train is over the switch, the address is stored in the EEPROM by encoding the identfying address into unique multi-bit check words.