Abstract: If a vehicle fitted with a head station is to be mechanically and electrically coupled to other vehicles, attention must be paid to the alignment of the vehicles and the coupling condition of the high frequency plugs interconnecting the vehicles. In order to reduce the labor and time required in the high frequency coupling of the vehicles, each vehicle, except for the one with the head station, is fitted with a vehicle station which is connected to the ends of the vehicles via paired high frequency lines by plug-in components. Before the high frequency signals are switched through in a vehicle, the vehicle station checks whether there is a high frequency signal and whether or not the plugs are coupled.