ANSWERS: 4
  • 1895 Few radio broadcasts travel through the air exclusively, while many are sent over telephone wires. In the 1860s, James Clerk Maxwell, a Scottish physicist, predicted the existence of radio waves, and in 1886 Heinrich Rudolph Hertz, a German physicist, demonstrated that rapid variations of electric current could be projected into space in the form of radio waves similar to those of light and heat. Guglielmo Marconi, an Italian inventor, proved the feasibility of radio communication. He sent and received his first radio signal in Italy in 1895. By 1899 he flashed the first wireless signal across the English Channel and two years later received the letter "S", telegraphed from England to Newfoundland. This was the first successful transatlantic radiotelegraph message in 1902. (Note: Nikola Tesla is now credited with having inventing modern radio; the Supreme Court overturned Marconi's patent in 1943 in favor of Tesla.) http://inventors.about.com/library/inventors/blradio.htm
  • As a supplement to another answer... Marconi developed the spark transmission system, which was unable to transmit voice. Instead, it used Morse code. Development work on the spark system continued until 1912, after which development focused on continuous wave radio systems. The first successful continuous-wave transmissions were made by Fessenden in 1900. Although they had a very limited range in comparison with spark systems, continuous wave systems allowed the transmission of voice and, later, music. CW systems saw substantial development by amateur radio operators ("hams") prior to WW1, by the military during WW1, and by commercial interests after.
  • Check with Marconi!
  • have no idea

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