Bending the Casio PT-87

This little keyboard can make some interesting sounds. Connect each pair of points with a potentiometer. An output can be fitted using a switching jack in parallel with the speaker. Remove the tune control if the pitch modification is applied. S is for scrambler, P is for pitch, D is for pitch drop and V is for overdrive. Use 100K potentiometers for everything but pitch, which needs a 500K potentiometer.