Modern Mechanix 1935
MODERN electronic engineers duplicate the music of a primitive marimba band with light beams, photo-electric cells and radio tubes. Dr. Phillips Thomas of the Westinghouse Research laboratory recently demonstrated a “light music” instrument which played by waving flashlights held in each hand.
Dozens of photo-cells and radio tubes are lined up side by side atop the new musical device. For each musical note there is an oscillating circuit which produces electrical vibrations when light is directed on that circuits photo-cell. Reproducers convert the electrical vibrations into sound which is directed into the marimba pipes.
Flashlight beams make music on photo-electric marimba – Link.
“Tales of Futures Past” – Link.