Conventionally, there has been proposed a remote operation device that operates an actuator from the outside of a cab in a working machine such as a mobile crane. In addition, there have been developed techniques and the like with which an auxiliary operation board connected to a control unit via a cable is provided separately from a main operation device disposed in a cab, and at the time of work that is hard to be visually recognized from the cab, a changeover to an auxiliary operation board is performed to operate an actuator.
For example, Patent Literature 1 discloses an operation device configured to be capable of controlling by an auxiliary operation board only when an overload preventing device is set to a jib overhang and storing mode, the operation device being configured so that a controllable range is limited to a range in which a crane operation needed to extend and store a jib is performed.