Sunday, December 11, 2005
The First Trans-Atlantic Wireless Broadcast, Dec. 12, 1901
Today in 1901, Italian radio pioneer William Marconi successfully sent the first trans-Atlantic radio transmission from Cornwall, England to Newfoundland, Canada. This experiment proved, once and for all, the practicality of radio for commercial use and helped to ensure Marconi’s place among those who helped contribute to the invention of wireless communication.
Marconi was born in Italy in 1874, the son of an Italian landowner and his Irish wife. He was well-educated for his day and soon became interested in the experiments of Heinrich Hertz and Nikola Tesla. These men, and many others, all worked in the field before Marconi. However, it is safe to say that, while other people claimed to have actually invented radio, it was Marconi’s system which first became available for widespread use.
In the last decade of the 19th century, Marconi and others demonstrated the ability to send and receive radio signals over ever-increasing distances. However, the great minds of the day claimed that wireless communications would forever be limited to a maximum distance of 200 miles. The reasoning was that since the Earth is round and radio waves travel in straight lines from their transmission source, at some distance the radio waves would leave the atmosphere and go straight out into space as the surface of the Earth curved away beneath them.
While this theory is true to some degree, scientists and engineers of the early 20th century had little or no understanding of the ionosphere, that level of atmosphere that is now used by radio transmitters all over the world to propagate their signal. While a radio wave will indeed head for space, it often bounces off the ionosphere and is sent back to Earth hundreds or thousands of miles from the point of origin. This explains why, at night, you can sometimes pick up radio stations that are half a continent away. Marconi did not have a hidden knowledge of the ionosphere; he was merely trying to find out far a radio wave would travel.
Modern critics of Marconi’s trans-Atlantic experiment claim that he almost certainly did not successfully transmit the Morse-code symbol for the letter ‘S’ across the ocean. There are two mains reasons for this conclusion: first, the time of day was wrong and two, the frequency Marconi used was not optimal. According to them, it is more likely that Marconi heard random background noise and mistook it for the signal coming from England. A transmission of such a distance is very difficult even today under the same conditions. Regardless, Marconi’s star was on the rise.
By 1903, the Marconi Company was transmitting news across the Atlantic (the distance could be easily bridged at night) and Marconi’s equipment was soon reliable enough to be placed aboard ships. He was awarded the Nobel Prize in physics in 1909, sharing the honor with Karl Braun. On the day of his funeral in 1937, all BBC stations around the world were silent for two minutes in his honor.