One of the Casiotone series of early home keyboards borrowed from a friend of a brother. I don't remember what you could do to modify the preset voices. Very little I think. There was a 'fill' button for the rhythms and you could split the keyboard to make the bottom half play one-touch chords or arpeggios. Wisely CA avoided these features. Is Mother Invisible? made full use of them. (Gerard)

See also
abject noise-makers