December 12, 1896…Marconi’s First Public Demonstration Of Radio

During his early years, Marconi had an interest in science and electricity. One of the scientific developments during this era came from Heinrich Hertz, who, beginning in 1888, demonstrated that one could produce and detect electromagnetic radiation…generally known as “radio waves”. At the time these were more commonly called “Hertzian waves” or “aetheric waves”. Hertz’s death in 1894 brought published reviews of his earlier discoveries, and a renewed interest on the part of Marconi.

Marconi began to conduct experiments, building much of his own equipment in the attic of his home at the Villa Griffone in Pontecchio, Italy. His goal was to use radio waves to create a practical system of “wireless telegraphy”…the transmission of telegraph messages without connecting wires as used by the electric telegraph. This was not a new idea—numerous investigators had been exploring wireless telegraph technologies for over 50 years, but none had proven commercially successful.

Marconi did not discover any new and revolutionary principle in his wireless-telegraph system, but rather he assembled and improved an array of facts, unified and adapted them to his system. At first, Marconi could only signal over limited distances. In the summer of 1895 he moved his experimentation outdoors. After increasing the length of the transmitter and receiver antennas, and arranging them vertically, and positioning the antenna so that it touched the ground, the range increased significantly. (Although Marconi may not have understood until later the reason, the “ground connections” allowed the earth to act as a waveguide resonator for the surface wave signal.) Soon he was able to transmit signals over a hill, a distance of approximately . By this point he concluded that with additional funding and research, a device could become capable of spanning greater distances and would prove valuable both commercially and militarily.

Finding limited interest in his work in Italy, in early 1896 at the age of 21, Marconi traveled to London, where he gained the interest and support of William Preece, the Chief Electrical Engineer of the British Post Office. A series of demonstrations for the British government followed—by March, 1897, Marconi had transmitted Morse code signals across the Salisbury Plain. On May 13, 1897, Marconi sent the first ever wireless communication over open sea.

Impressed by these and other demonstrations, Preece introduced Marconi’s ongoing work to the general public at at an important London lecture: “Telegraphy without Wires”, at the Toynbee Hall on December 11,1896. The next day, Marconi returned with a tramsmitter and telegraph key, and a wooden box with a bell inside. With the London press in attendance, Preece walked around the hall with a wireless wooden box which magically rang every time Marconi hit the key.

Numerous additional demonstrations followed, and Marconi began to receive international attention. In July 1897, he carried out a series of tests at La Spezia in his home country, for the Italian government. A test for Lloyds between Ballycastle and Rathlin Island, Ireland, was conducted on 6 July 1898. The English channel was spanned by radio on March 19, 1899, from Wimereux, France to South Foreland Lighthouse, England, and in the fall of 1899, the first demonstrations in the United States took place, with the reporting of the America’s Cup international yacht races at New York.

On December 12, 1901, Marconi sucessfully sent a wireless telegraph message from Cornwall in southwest England to St. Johns Nova Scotia. By sending a signal more than 2,100 miles across the Atlantic, Marconi convincingly demonstrated the practicality of worldwide wireless communication. And in 1909, he shared the Nobel Prize for physics with Karl Ferdinand Braun of Germany, whose modifications to Marconi’s transmitters made them strong enough to be practical.

Below is a photo of Marconi (R) with David Sarnoff (L), head of RCA. Sarnoff had once worked for the Marconi Company in New York and was the telegraph operator that received the Titanic SOS and communicated with the rescue ships until they arrived in NY with the survivors. -Bobby Ellerbee

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