The radio was developed because of two closely connected inventions – the telegraph and the telephone. All the three technologies are very closely related to each other. The technology used to develop the radio has its roots in “wireless telegraphy”. The word “radio” can be used to convey the actual electronic device, which we listen to, and it can also mean the programs, music, and other transmissions broadcasted by radio stations. It all began with the discovery of electromagnetic waves. These waves have the ability to transmit pictures, music, and speech through the air. Electromagnetic waves are not visible to the naked eye. Many electronic devices such as cordless phones, microwaves, television broadcasts, remote controlled toys, etc. utilize electromagnetic waves.
The origin of radio
James Clerk Maxwell, the Scottish physicist, stated that radio waves existed in nature, in the 1860s. Later, in 1886 a German physicist called Heinrich Rudolph Hertz exhibited that frequent variations in electric current could be transmitted into space through waves which are similar to light and heat waves. In the same year, an American dentist Mahlon Loomis demonstrated the existence of “wireless telegraphy”.
The growth of radio and radiotelegraph
Radiotelegraphy involves transmitting radio waves in the form of dots and dashes as used in sending Morse code in the form of a telegraph. In those days, transmitters were physically huge, and called “spark gap machines”. The technology was mainly developed for use by ships. Radiotelegraphy was originally used to set up communications between ship-to-ship and ship-to-shore. Signals, which could be transmitted without the use of cables or wires i.e. wireless signals, proved to be very useful while carrying out rescue work in the seas. Later, many steamers and ocean liners installed wireless sets. The United States armed forces started establishing wireless communications near Fire Island, New York in 1899. Two years hence, the entire Navy started using wireless technology for its functioning. Radiotelegraph service was established within the Hawaiian Islands in 1901. In 1903, a primitive radio station in Wellfleet, Massachusetts, transmitted a greeting message between King Edward VII and President Theodore Roosevelt. The Russo-Japanese naval war of Port Arthur in 1905 was made public using wireless telegraphy. By 1906, the U.S. weather department started using radiotelegraphy to announce the changes and updates in weather conditions. Robert E. Peary the arctic explorer radio telegraphed the message “I found the Pole” in 1909. Marconi opened the American-European radiotelegraphy services in 1910. The services helped to capture an escaped British convict many months later. The first trans-pacific radiotelegraph service joined San Francisco with Hawaii in 1912.