Abstract: A small-sized lightweight portable hand-held housing is provided with elements for visually displaying selected combinations of information quantities such as musical notes of scales and chords. The displays are operated by signals from programmable read only memory elements in the housing. Manually operable selector elements such as push button switches on the housing are used to select particular combinations to be displayed. A circuit including digital logic elements converts manual operation of a selector element into operation of appropriate memory elements to activate the displays.