Abstract: An analogue display has a circle of electrically-energizable elements that are selectively energized so as to represent time. A rotatable setting wheel has a knurled edge that projects from the display casing. A leaf spring engages the knurled edge, the spring having a piezo-electric element on its surface which produces pulses dependent on rotation and direction of rotation of the wheel. Different elements are energized around the circle, as the wheel is rotated, according to the speed and direction of rotation. A second value, such as temperature, can be represented if each element extends radially and is divided into separate sub elements. By energizing different numbers of the sub elements, the apparent radial length of the element can be varied to represent the second value.