Radio owes its development to two other inventions, the telegraph and the telephone; all three technologies are closely related. Radio technology began as “wireless telegraphy”.
Radio can refer to either the electronic appliance that we listed with or the content listened to. However, it all started with the discovery of “radio waves” – electromagnetic waves that have the capacity to transmit music, speech, pictures and other data invisibly through the air. Many devices work by using electromagnetic waves including: radio, microwaves, cordless phones, remote controlled toys, television broadcasts, and more.
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.
THE ROOTS OF RADIO
During the 1860s, Scottish physicist, James Clerk Maxwell predicted the existence of radio waves; and in 1886, German physicist, Heinrich Rudolph Hertz 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.
In 1866, Mahlon Loomis, an American dentist, successfully demonstrated “wireless telegraphy”. Loomis was able to make a meter connected to one kite cause another one to move, marking the first known instance of wireless aerial communication.
By 1903, a Marconi station located in Wellfleet, Massachusetts, carried an exchange or greetings between President Theodore Roosevelt and King Edward VII. In 1905 the naval battle of Port Arthur in the Russo-Japanese war was reported by wireless, and in 1906 the U. S. weather Bureau experimented with radiotelegraphy to speed notice of weather conditions. In 1909, Robert E. Peary, arctic explorer, radiotelegraphed: ” I found the Pole”. In 1912, the first trans-pacific radiotelegraph service linked San Francisco with Hawaii.
What is Radio Astronomy
Many astronomical objects emit radio waves, but that fact wasn’t discovered until 1932. Since then, astronomers have developed sophisticated systems that allow them to make pictures from the radio waves emitted by astronomical objects. A number of celestial objects emit more strongly at radio wavelengths than at those of light, so radio astronomy has produced many surprises in the last half-century.
Today, there are more than 33,000 radio stations around the world, with more than 12,000 in the US alone. Worldwide there are more than 2 billion radio sets in use, or about one radio for every 3 persons; proof that video never killed the radio star.