Visual and audible indicator for learning musical scales - contains slide carrying musical note indications on scale which selects contacts in oscillator circuit

摘要

The body (1) in the form of a cross has one arm (2) which forms a box for various circuit components in an oscillator and modulator circuit. The arm carries contacts (3) which are selected by a push button (19). This arm also acts as a guide for a slide (4). The other arm (5) comprises part of the first arm and consists of plates (6,7) carrying a musical scale. The plates have grooves (8,9) perpendicular to the scale lines and in which notes (10,11) are indicated. These notes are carried on the arms on the slide which locate behind the scales. As the slide moves up or down the notes also move. The push button selects the contacts which ensure the oscillator output to a loudspeaker generates the corresponding musical note.