Improved Radio Transmitter: Fessenden sends the first audio radio transmission
Canadian-born Reginald Fessenden (1866-1932) caused a landmark in the development of radio when he transmitted his own voice over radio waves late in 1900, a feat not even Marconi had achieved. At the time, Fessenden was working for the United States Weather Bureau to develop wireless technology for weather forecasting. On December 23, at his station on Cobb Island, Maryland, Fessenden transmitted what is considered what is considered the first wireless transmission carrying audio sound. “Hello, one, two, three, four. Is it snowing where you are Mr. Thiessen? If it is, telegraph back and let me know,” he shouted into the microphone. Thiessen excitedly telegraphed back that it was.
The transmitter that Fessenden used was a spark transmitter, a device developed in the late nineteenth century by radio pioneers Hertz, Marconi and Braun to generate radio frequency electromagnetic waves. Fessenden had modified it so that the sparks produced more continuous waves rather than ones that died away quickly. He also placed a carbon microphone directly in series with the antenna lead. He applied for a United States patent for the transmitter in 1901 and it was the first to use the same principles that AM (medium wave) radio stations use today.
This milestone was only the start of the influence Fessenden was to have on radio history. After further improvements to his transmitter, he made the first transatlantic voice transmission from Massachusetts to Scotland, as well as the world’s first radio broadcast on Christmas Eve, 1906. The broadcast consisted of music and readings and was heard mostly by ship operators, some as far away as the West Indies.