 However, as the Great Depression continued into the 1930s, sales of the bridge table declined and he decided to look elsewhere for a commercially successful product.Hammond was inspired to create the tonewheel or "phonic wheel" by listening to the moving gears of his electric clocks and the tones produced by them.He gathered pieces from a second-hand piano he had purchased for $15 and combined it with a tonewheel generator in a similar form to the telharmonium, albeit much shorter and more compact.