the invention relates to a network station comprising a selector switch for coupling a switching center to a pots or isdn telephone , and a detection circuit . after the detection circuit has been made operative or after the mode change from the pots mode to the isdn mode , the detection circuit controls the selector switch such that this switch goes to the isdn mode and thus couples the switching center to an isdn network terminator . when the isdn mode is changed into the pots mode , the selector switch is actuated by the detection circuit so that the switch couples the switching center to the pots telephone .