An input apparatus capable of concurrently accommodating itself to any external signal from a different hydraulic control system or the like. The apparatus includes electrical load sensors each arranged on a push rod or block for detecting the amount of operation of a control lever to generate an electrical signal corresponding to the amount of operation of the control lever. Also, an input apparatus which is capable of concurrently responding to both a signal generated by itself and an external signal fed thereto is provided. The apparatus includes a pilot section for exerting force which permits a shuttle to be moved against coiled compression springs. The pilot section is fed with a signal from an external hydraulic control system.
