Abstract: The faceplate of the display system carries the outlines of a sequence of computer compatible digits. Each digit consists of four binary weighted line segments, each segment is associated with a hole in the faceplate. Holes are in line and equally spaced. Behind the faceplate a slide bearing Leds moves along the line of holes. For each operating position the Leds appear behind a set of successive holes. The Leds receive the digital output of the instrument. The arrangement is such that movement of the slide by one position changes the scale by a factor of two. A switch associated with the slide causes the measuring range of an associated instrument to be simultaneously changed by that same factor of two.