Abstract: An input keyboard (1) contains a switching device (3) for pushbuttons (22) wherein the contact linings (11.1, 11.2) on a printed circuit board (10) are bridged by a countercontact (16) operated by the pushbutton (22). The countercontact (16) consists of a carbonized plastic foil (14) and an electrically conducting layer (17) on the side facing away from the contact linings. By virtue of this arrangement there comes into being a bridging resistance between the bridged conductor strips (12.1, 12.2) that depends on the operating pressure (P) applied to the pushbutton, this resistance being then used to cause a control circuit arrangement (6) to generate a control command (Bf) for setting a particular function and an adjustment command (Bw) for setting a particular value or adjustment rate.