• History
• Demand develops to develop a wireless telegraph
• Useful at sea; no expense of wiring
• [no though of general broadcast]
• Tesla- wants to talk with the Dead, needs refined instrument
• Marconi (1896) patents "wireless"
• Sea Communication to Military Device
• Can the public even use it? (Susan Douglas, historian)
• Material Side
• James C. Maxwell- Electro-magnetism equations worked out (1880s)
• [the Newton of electro-magnetic world?]; Hertz explores frequency
• transmission/propagation of energy in the form of waves-
• same speed
• Modulating Waves-
• Frequency (how long a cycle); Amplitude (how large a cycle)
• Spectrum- the range of waves-
• infrared, radio, visible light, ultraviolet, x-ray, gamma-ray
• continuous- an example of analog
• Photons? What about discrete entities with energy (digital)
• Different ways of approaching the same thing?
• Amplifying- Lee DeForest
• (vacuum tube) 1906 amplifies sound- key device
• provides the way for lower cost receivers and transmitters
• Improved Modulating- Frederick Armstrong (1933)
• Improves amplifying (lawsuits); invents FM to reduce static
• Invents multi-plexing capable of stereo broadcast
• Sets up first FM station- sabotaged by FCC on behalf of RCA
• Driven to suicide by RCA and big business (remember Gutenberg?)
• Digital Radio- (would have to await computer and digital infrastructure)

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