Last update 4/19/961820 - Hans Christian Oersted discovers Electromanetic Induction while giving a lecture and demonstration. - Andre M. Ampere laid the foundations for the science of electrodynamics demonstrating that electrical currents produce magnetic lines, and the relation between the two.
1826 - Joseph Henry is best known for his discovery of electromagnetic induction and self induction. The unit of Inductance, the Henry was named in his honor.
1831 - Michael Faraday demonstrates the principle of Induction. His research into electricity lead him into the field of electromagnetism. That current flowing through a wire produced magnetic lines of force around that wire.
1836 - Ampere dies in June
1851 - Hans C. Oersted dies in March.
1852 - Edison invents the automatic telegraph.
1864 - James C. Maxwell developed Maxwell's Equations which were an extension and mathematical formulation of Faraday's theories of electricity and magnetic lines of force.
1867 - Faraday dies in August.
1868 - Edison invents the stock ticker. - Amos Dolbear while a professor at Bethany College invented the electrostatic telephone. Dolbear also work on converting sound waves into electrical impulses.
1873 - James C Maxwell publishes a book on electricity and magnetism.
1875 - Charles Coulomb demonstrates the manner in which electric charges repel each other.
1877 - Edison invents the phonograph.
1878 - Joseph Henry dies in May.
1879 - James C. Maxwell dies
1882 - Edison develops the first central electric light power station. - Professor Amos E. Dolbear was able to communicate over a distance of a quarter of a mile without wires in 1882. It is interesting to note that Prof. Amos Dolbear preceded Hertz and Marconi.
1887 - German physicist Heinrich Hertz first discovers Radio Waves. He transmitted an electrical spark which was heard in a receiving circuit a few meters away, thus the term Hertzian Wave. Hertz demonstrated that the elocity of radio waves equaled the speed of light. The unit of frequency was named in his honor.
1894 - Marconi first experiments with Hertzian Waves. - Heinrich Hertz dies in January.
1895 - Marconi uses the oscillators of Hertz and Righi. The signals were too weak so Marconi connects the oscillator to antenna and ground to increase power. It is also in 1895 when Marconi sends his first wireless radio transmission at Pontecchio, Italy. Three dots (the letter "S") were heard behind the hill three kilometers away.
1896 - Marconi leaves for London, Marconi performed his first offical experiment from the terrace of the Post Office to the Salisbury plain. He was granted the worlds first radio patent.
1897 - The British Ministry gives Marconi money and technicans to continue his work. Marconi signals reached 5, 8, 15, 30 and 100 km. In July Marconi formed the Wireless Telegraph Trading Signal Co. LTD. - Edison develops the first practical incandescent lamp.
1898 - For the first time telegraph is used to send a help signal from a lighthouse boat in August. In September Marconi comes to the US where he carries out a telegraph circuit for the Navy between the cursers New York and Massachusetts. First wireless used for journalism for the Daily Express.
1899 - Marconi is granted patent no. 7777 for his Tuning equipment. He also proved through experiments that the curvature of the Earth was not an obstacle with his 32 mile connection from England to France.
1900 - The Wireless Telegraph Trading Signal Co. Ltd changes its' name to the Marconi Telegraph Co. Marconi gets his English patent for his Tuning equipment.
1901 - Marconi receives a weak signal, the letter "S", the first signal to cross an ocean, from Poldhu, Cornwell, England, to St. John's Newfoundland, Canada. To give you some idea of the size of the station, power for one of the stations was provided by a 75 kw alternator driven by a coal-fired steam engine. The antenna was an inverted pyramid of copper wires supported by four latticework towers that were 210 foot high.
1902 - Marconi builds a radio station at Glace Bay, N.S. It is during the trip that he discovers the harmful influence of solar radiation on tramissions. Thus the creation of the Magnetic Detector. The station at Glace was set up as the transmitting station, while the station in Europe at Poldhu was the receiving station. They would use the cable line as a means to verify communications between the two stations. On December 15th the first offical messages came through from Table Head to Poldhu saying "we have received some sginals".
1903 - Marconi establishes the first press agency between Europe and America. Jaunary 18th the first two-way transatlantic transmission between Poldhu, England and Cape Code Mass. USA.
1904 - Fleming invents the thermionic valve. Marconi built the Rotating Oscillator and discovered the directive properties of horizontal antennas. Starts to use the Fleming thermoionic valve.
1905 - Fleming developed the first diode known as the Fleming Valve. - Marconi patented his directive horizontal antenna. - DeForest invents the audion.
1906 - 27 nations signed the International Wireless Telegraph Convention in Berlin. - Greenleaf Pickard invented the silicon detector. - Reginald Fessenden broacsast the first program of speech and music transmitted by radio. He was also know for his inventions of the heterodyne system of radio, sonic depth finder, radio compass and others.
1907 - Clarence D. Tuska the first Secretary of the A.R.R.L. started working with the Coherer. - Marconi, Commerical transatlantic wire service inaugurated between Glace Bay and Clifton Ireland. - DeForest invents the audion also known as the triode. He was granted over 300 patents in the field of wireless, radio, telephone, sound-on-film, picture transmission and T.V.
1909 - Marconi is awarded the Nobel prize for Physics.
1912 - Marconi invents a new way to generate a continuous wave, known as the Multiple Spark System.
1913 - Clarence Tuska received his first Amateur station and Commerical Operators Lic. - The antenna at the Marconi site at Louisbourg was about 1 kilometer long, and was supported by six tublar steel towers over 3000 ft high.
1914 - In the spring a small group of young Amateurs were using short ranged spark coils. - According to the records, in January Hiram Percy Maxim called to order the first meeting of the Radio Club of Hartford with some 23 members in attendance. By March the attendance grew to 35 members. It was then that H.P.M. had the idea that messages could be relayed over great distances. In order to accomplish this, a network would have to be set up across the country. With this in mind, the American Radio Relay League was adopted and formed. In October the newly formed league published its' first callbook which listed some 400 stations in 33 states and Canada. - Marconi experiments successfully using the triode thermoionic valve, this was the birth of radiophony.
1915 - Control of the A.R.R.L. was taken over by H.P.Maxim and Clarance D. Tuska, the first Secretary of the League. The League was incorporated, and the second callbook was issued containing almost 600 members. The league published the first issue of QST in December.
1916 - League membership jumped to around 960 members. It was in 1916 that the league made its' attempt at a nation-wide relay. 9XE of Davernport Iowa, on Washingtons birthday, sent a message from the Rock Island Arsenal addressed to the goveners of every state and President Wilson. The relay time wasn't too bad. The record exhibits that the message got to the Pacific coast in 55 mins, to the Atlantic Coast in 60 mins, to New Orleans and Canada in 20 mins. By this time Amateurs were establishing reliable trunk networks across the US. By the end of 1916 six trunks had been established. Also in 1916 the first transcontinental attempt was tried and failed due to static. - Marconi started to develope the first VHF radios.
1917 - A second transcontinental attempt was made in January and was successful. The message was sent by 6EA took 3 relays to H.P.M. station in Hartford, Ct. In February a two-way circuit was accomplished in one night. Amateur Radio closes down due to the WAR.
1918 - Thousands of Amateurs pound brass for the Army and Navy during the War.
1919 - Marconi acquires the yacht Elettra for radio experiments. - Amateur Radio resumes after the WAR, and thousdands of Hams renew their A.R.R.L. membership.
1920 - QST carries an editorial on CW vs SPARK as Amateurs take sides.
1921 - The second transatlantic test is run and is a success. This spells the end of Spark as the Audion tube takes its' place.
1922 - There were over 15,000 licensed Amateur stations.
1927 - Legislation curtails spark-gap transmissions.
1931 - Marconi inaugurates the new Vatican Radio Station. He further demonstrated the possibility of using micorwaves communicating between Santa Margherita Ligure and Levanto 36km away. - Edison dies in October with more than 1000 patents to his credit.
1932 - Marconi builds a permanent radiotelegraph connection between the Vatican and Castel Gandolfo.
1934 - Marconi establishes a radiotelegraph link between the Elettra and the radio beacon in Sestri Levante.
1937 - July 20th Marconi dies, Radio Transmitters around the world close down for two minutes in his memory.
1945 - Fleming dies in April.