1936 – Edwin Armstrong presented FM radio at FCC headquarters. Armstrong played a jazz record over conventional AM radio, then switched to an FM broadcast. “[I]f the audience of 50 engineers had shut their eyes they would have believed the jazz band was in the same room.”
http://www.princeton.edu/~achaney/tmve/wiki100k/docs/FM_broadcasting_in_the_USA.html
1946 – The first mobile telephone call was made from a car in St. Louis, Missouri. Teams from Bell Labs and Western Electric had collaborated to develop the technology.
http://ethw.org/The_Foundations_of_Mobile_and_Cellular_Telephony
1997 – Programmers deciphered code written in the impenetrable Data Encryption Standard, the strongest legally exportable encryption software in the United States. The hackers organized over the Internet and cracked the software in five months, proving that stronger encryption was needed.
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