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			Lee Deforest Born Aug 26 1873 - Died Jun 30 1961 Space Telegraphy Radio Patent Number(s) 879,532 Inducted 1977 In the early 1900s, the great requirement for further development of radio was an efficient and delicate detector of electromagnetic radiation. Lee de Forest provided that detector. DeForest found a clue to creating the long-sought detector of electromagnetic radiation in John A. Fleming's invention of the so-called electronic valve. The most serious drawback of the Fleming valve was that it was relatively insensitive to changes in the intensity of incident electromagnetic radiation. Moreover, the Fleming valve could act only as a rectifier, not an amplifier. DeForest's simple but revolutionary answer was to insert a third electrode between the cathode and the anode. The audion amplifier was the most important of de Forest's more than 300 patents. Invention Impact DeForest’s audion was used for many different purposes such as a detector for radio signals, an amplifier of audio, and an oscillator for transmitting currents. The Audion was used to transmit radio waves from radio frequency (RF) to audio frequency (AF). This allowed radio waves to be heard through headphones or even broadcast via loudspeaker. The audion has been most famously used in long-distance telephone service as it enables sound to travel over wireless communication systems. DeForest’s audion vacuum tube was the key component of all radio, telephone, radar, television, and computer systems before the invention of the transistor in 1947. Inventor Bio Born at Council Bluffs, Iowa, de Forest at an early age exhibited the inventive talents that were to make him famous. His father sent him to the Mt. Hermon (Massachusetts) School for Boys and from there he entered Yale University. While in college, he continued to invent-an improved typebar movement for his typewriter, an improved compass joint, a 'puzzle game'-all to help defray his expenses. After receiving his B.S., he continued his studies at Yale and received his Ph.D. in 1899. De Forest's doctorate thesis was on the "Reflection of Hertzian Waves from the Ends of Parallel Wires"; thus began his long career in radio