Look, Ma, No Wires!


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Professor Mindy McAdams's presentation about the invention of wireless telegraphy and the beginning of radio

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  • Look, Ma, No Wires!

    1. 1. Look, Ma, No Wires! Presentation by Mindy McAdams Tuesday, Week 11
    2. 2. 1909: The first transatlantic radio telegraph service began, thanks to the Marconi Wireless Telegraph Company (founded by Guglielmo Marconi). 1911: The Titanic set out on its maiden voyage April 10. She struck an iceberg on the night of April 14 at 11:40 p.m. and sank at 2:20 a.m.
    3. 3. What the Titanic Tells Us <ul><li>Before the wireless telegraph, there was virtually no way for a ship at sea to communicate with: </li></ul><ul><ul><li>Other ships </li></ul></ul><ul><ul><li>Land </li></ul></ul><ul><li>The ship that rescued survivors had to come through the ice for two hours before reaching them (it was 58 miles away) </li></ul><ul><li>On the ship that could have saved them (19 miles away), the wireless was turned off for the night </li></ul>
    4. 4. A Sense of Connection <ul><li>People around the world (or at least, people in the U.S. and Europe) felt as if they were connected to the Titanic disaster </li></ul><ul><li>Simultaneous experience across a far distance: This was new </li></ul><ul><li>Today we say: “In real time” </li></ul><ul><li>Today we call events “synchronous” or “asynchronous” </li></ul>
    5. 5. Electric Communication <ul><li>1837: The electric telegraph (required a wire) </li></ul><ul><li>1876: The telephone </li></ul><ul><li>1895: The wireless telegraph (the first broadcasting) </li></ul><ul><li>1906: Radio brought instant long-distance communication to a mass audience for the first time </li></ul>
    6. 6. Guglielmo Marconi (1874 – 1937) <ul><li>1909 Nobel Prize in Physics (shared with Karl Ferdinand Braun, German, b. 1850) </li></ul><ul><li>His goal: Use radio waves to create a system for sending telegraph signals without wires </li></ul><ul><li>Marconi’s system sent Morse code </li></ul><ul><li>He was Italian, but could not drum up interest in Italy </li></ul><ul><li>Traveled to England (he was only 21) and found support there </li></ul>
    7. 7. Guglielmo Marconi (2) <ul><li>In March 1897, Marconi transmitted wireless signals across about 4 miles across the Salisbury Plain, England </li></ul><ul><li>In March 1897, he transmitted wireless signals across the Bristol Channel (8.7 miles) </li></ul><ul><li>1899: First wireless demonstrations in the U.S. – they carried reports of the America’s Cup yacht races from New York </li></ul>The Shamrock and the Columbia racing for the America’s Cup, New York Harbor, 1899
    8. 8. This is the Marconi wireless telegraph, as it was installed on a yacht, to cover the America’s Cup for the New York Herald newspaper in October 1899 Source: Dalhousie University
    9. 9. Across the Atlantic <ul><li>December 1901: Marconi reportedly received a signal in St. John’s, Newfoundland , sent from one of his stations in Cornwall, England (about 2,100 miles </li></ul><ul><li>1907: Regular transatlantic service was announced, but communication was not reliable for many years </li></ul><ul><li>1904: Wireless transatlantic news service, from Cornwall to Cape Cod, Mass. </li></ul>
    10. 10. First Radio Broadcast (AM) <ul><li>1906: Reginald Fessenden transmitted it </li></ul><ul><li>Sent from Brant Rock, Mass. </li></ul><ul><li>Ships at sea heard it </li></ul><ul><li>Fessenden played the song Silent Night on a violin and read a passage from the Bible </li></ul><ul><li>Fessenden had made his first wireless audio transmission in 1900 </li></ul><ul><ul><li>From Cobb Island, Md., on the Potomac River </li></ul></ul><ul><ul><li>It was heard about 1 mile away </li></ul></ul>
    11. 11. Radio in the 1920s <ul><li>“ Crystal sets” used to pick up radio signals </li></ul><ul><li>A popular hobby </li></ul><ul><li>A period, at least in the U.S., similar to the early days of the personal computer </li></ul><ul><li>Three stages: </li></ul><ul><ul><li>“ DXing” </li></ul></ul><ul><ul><li>Music listening </li></ul></ul><ul><ul><li>Story listening </li></ul></ul>
    12. 12. Look, Ma, No Wires! Presentation by Mindy McAdams University of Florida