A scroll displaying mechanism suitable for use in moving advertising displays, chart recorders and tape readers uses a pair of D.C. motors wired to operate under slightly different speed-controlling voltages in order to maintain the displayed part of the scroll between two rollers taut. A simple belt and pulley drive mechanism for each roller assures quiet and vibration-free operation. The viewing time between frame-advance and the scroll direction reversal are controlled by detection of different length markers positioned along one edge of the scroll.
