The prolific American inventor Lee De Forest (1873-1961) is one of several pioneers of radio development. De Forest experimented with receiving long-distance radio signals and in 1907 patented an electronic device named the audion. Until this time, the radion was considered little more than "wireless telagraphy," since it sent Morse code (dots and dashes) instead of conveying actual sound. De Forest's new three-electrode (triode) vacuum tube boosted radio waves as they were received and made possible what was then called "wireless telephony," which allowed the human voice, music, or any broadcast signal to be heard loud and clear.

An example of De Forest's schematic diagrams and notes scribbled hurriedly on hotel stationary around 1915.

Lee De Forest - Space Telegraphy
Lee De Forest invented space telegraphy - National Inventors Hall of Fame.

Lee DeForest
Lee DeForest invented the triode amplifier and space telegraphy - Invention Dimension.

Lee De Forest
The live of Lee De Forest, American inventor of the Audion vacuum tube, which made possible live radio broadcasting and became the key component of all radio, telephone, radar, television, and computer systems before the invention of the transistor in 1947.

The De Forest Reflex Radiophones
Dave Gonshor's description of the De Forest reflex Radiophone models provides another glimpse of Lee de Forest's bumpy ride through radio history.

Related Innovations
Radio

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