Abstract: A cam-actuated microswitch unit has cams the positions of which can be varied relative to a drive shaft to vary the switch-actuating point. The unit includes a plurality of microswitches rigidly connected to a support while the cams are frictionally retained in a selected angular orientation on the drive shaft which can be connected to a measuring instrument so that its angular orientation is representative of the magnitude of a physical quantity to which the instrument is sensitive. The cams are connected to index pointers which can be moved over a movable scale fixed for rotation with the drive shaft to determine and to display the switch point settings.