William Gilbert 1544-1603
Born in England, he served Queen Elizabeth I as a physician. During his lifetime he performed many experiments on the nature of magnetism, and eventually offered the first comprehensive theories of magnetism, based on his assumption that the Earth itself was a large magnet.
Modern aircraft pilots are well aquatinted with at least two of his findings, Magnetic Dip, and Magnetic Variation of a compass.
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James Clerk Maxwell 1831-1879
Maxwell was born in Edinburgh, Scotland and was the founder of electromagnetic theory. He built upon the works of Faraday, Thomson, Coulombe and Ampere - and eventually developed a field theory of electromagnetic phenomena. Maxwell suggested that when a current began to flow, it caused a series of vortices in the surrounding Aether. The crux of his work stated that only in a steady state can a magnetic field exist without causing an electric field - and vice-versa.
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Guglielmo Marconi 1874-1937
Probably the name associated most with the invention of radio, Marconi was certainly a visionary of what it could become. Born into a very well-to-do family in Bologna, Italy, Marconi first read of the pioneering work in radio in 1894, in an obituary of Heinrich Hertz. He was the first to realized the possibility of using this new technology as a form of communication, and he began his life work. Within the year he was ringing a bell by wireless control a few yards away, and by 1897 the distance spanned by his wireless was nearly 10 miles.
Among his innovations were a greatly improved 'coherer' or detector, antenna work - including an earth ground which greatly increased his range, and the use of a high antenna. A vertical antenna with an earth ground is still referred to as a 'Marconi'. He also worked with directional antenna's.
At the age of 22 he filed for his first patent (#7777) for a system of radio communication. Five years later he succeeded in signaling across the Atlantic Ocean.
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Mahlon Loomis 1826-1886
Born in New York, and a dentist by profession Mahlon Loomis became interested in electricity and conducted several experiments on the effects of electricity on plant growth. His work on wireless communication - although not actually radio communication - could well have been more important had it not been for the economy of the day. He never had the financial backing to continue his work.
Among his other experiments were attempts to replace batteries with electricity taken from the atmosphere - he planned to fly kites attached to long wires to gather this electricity.
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Thomas Alva Edison 1847-1931
Edison was born in Milan, Ohio in 1847. A prolific inventor - in 1879 he developed the first commercially practical incandescent lamp. By 1882 he had developed a central power station for his lamps - necessary before they would become widely used. He invented the Stock Ticker, alkaline storage batteries, the carbon microphone and of course, the phonograph. In all, over 1000 of his inventions held patents - including a method of wireless telegraphy based on magnetic induction.
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Edwin Armstrong 1890-1954
Born in New York City, Armstrong graduated from Columbia University in 1913, and received his first patent for his regenerative receiver in 1914.
Without a doubt, Edwin Armstrong did more to advance the art of radio than any other inventor. Every radio and television receiver uses Armstrong's inventions. His list of patents and inventions includes regeneration, the superheterodyne receiver, and wide-band FM. During war time, Armstrong freely gave use of his patents to the military. From 1931 his efforts went into developing and promoting FM, and defending his inventions against suits by DeForest. Many years later almost every suit was decided in favor of Armstrong.
Armstrong committed suicide in 1954.
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Lee DeForest 1873-1961
Born in Council Bluffs, Iowa to a Congregational minister, Lee Deforest made his greatest contribution to radio and electronics with his invention of the Triode. Although he flooded the patent office with ideas, only a relative few of his over 300 patents proved important.
In the early years of radio he installed many wireless transmitting stations, and his became one of the most famous of the early companies. His business sense however, was lacking, and he was taken advantage of by several associates.
He concentrated his efforts on moving pictures in the 1920's - claiming the field of radio was getting too crowded. Later years found him suing other inventors - notably Howard Armstrong - for patent infringement.
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Heinrich Hertz 1857-1894
Hertz was born in Hamburg, Germany and attended the University of Berlin. In 1883 he became an instructor at Kiel University - where he first studied the work of Maxwell.
Maxwell had theorized that electric fields in the form of waves propagated at the speed of light rather than instantaneously. To prove this, Hertz conducted a series of experiments between 1886 and 1889 involving measuring the strength of oscillations at differing points along a sheet of zinc. These experiments confirmed the existence of waves, and that these waves acted identical to light in regards to refraction and polarization. In short, Hertz had proven the theory of Maxwell that light itself was a form of electromagnetic radiation.
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John Ambrose Fleming 1849-1945
Fleming was born in Lancaster, England and studied electricity and mathematics under James Clerk Maxwell. He served a number of electric lighting companies as advisor and engineer, and was a scientific consultant for the Marconi Company from 1899-1905. Besides his work in theory, he was also active in the practical application of his work. He made improvements in electric lamps, generators, and many pieces of radio-telegraph apparatus.
In 1904, while searching for a better detector for wireless signals he recalled his work for Edison in the early 1880's - and the phenomenon known as the Edison Effect. He fashioned a lamp with a metal cylinder surrounding the filament, ran wires to the outside of the envelope - and started the industry of electronics with his electrical 'valve'.
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Nikola Tesla 1856-1943
Tesla was born in Croatia, but moved to the United States in 1884. Following his move he worked for Thomas Edison designing dynamos, and then established his own laboratory in 1887.
Tesla's work laid the foundations for large scale electric power generation and transmission. Tesla experimented with high frequency alternators and invented the 'Tesla Coil' as a means for even higher voltages. His work included the forunner of the neon and fluorescent lights, he predicted radio as a means of communication in 1893, and spent a large amount of time in an effort to transmit electric power without wires. He built the largest Tesla coil ever made at Colorado Springs - a twelve million volt device which drew an arc up to 135 feet in length.
Other predictions by Tesla included radar in 1917, and radio services of pictures, time, and weather information in 1900.
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Karl Ferdinand Braun 1850-1918
Born in Germany, Braun shared the Nobel Prize in physics with Marconi in 1909 for their service in developing wireless telegraphy. His wireless equipment utilized resonant circuits in both the transmitter and receiver circuits, greatly improving upon Marconi's original system.
Braun later introduced the use of the crystal detector in receivers. His work on observing waveforms using a phosphor-coated screen paved the way for cathode ray tubes, and eventually the television picture tube.
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Edouard Branly 1844-1940
A French physicist and physician who's studies of nerve impulses led him to develop the 'coherer' as a device for detecting radio signals. His device was a glass tube filled with metal filings and two electrodes. The device decreased in resistance in the presence of electrical energy, as the filings stuck together - or 'cohered'. Many coherers utilized a small hammer-like device to tap the tube after each signal, breaking up the filings and increasing the resistance in preparation for the next signal. Marconi utilized the coherer in most of his wireless station in the early 1900's, and openly credited Branly for his invention.
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Reginald Aubrey Fessenden 1866-1932
Fessenden, a Canadian born in East Bolton, Quebec worked as a tester and Chemist in the Edison Machine works of New York, and later at Edison's laboratory in New Jersey. Among his patents were the electrolytic detector - far more sensitive than other early methods of detection, and the process of 'heterodyning' a signal - mixing it with another frequency to create a 'sum' and 'difference' of the original frequency.
Personally, he is said to have been a bit arrogant - using phrases such as 'Don't try to think - you haven't the brain for it'.
He obtained over 500 patents in his lifetime, many for advances in the art of radio.
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Joseph Henry 1797-1878
Joseph Henry served as the first director of the Smithsonian Institution from 1846-1878. He was born in Albany, New York, and attended Albany Academy - even though his primary and secondary education were sub-standard. Upon reading a popular book on science he determined to make that his work, and began to study to gain entrance to the Academy.
Henry's experiments with electromagnets allowed Faraday and other to have improved tools for their research. He greatly improved upon the electromagnet with the use of insulated wires, and is credited with having discovered inductive resistance. In fact, the unit used to measure inductive resistance is the 'henry', in his honor.
Henry also invented an electric motor in 1829, a telegraph in 1831, and the relay in 1835. He went on to work with transformers and non-inductive windings.
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Werner Siemens 1816-1892
Born into a family of engineers and inventors, Werner and his younger brother William developed the Dynamo - a device which converted mechanical energy into electrical energy by using 'self excitation', eliminating the use of permanent magnets. This led to the birth of the commercial power industry.
Werner also invented an electroplating process, and a method of insulating electrical cable suitable for underwater telegraph cables.
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Michael Faraday 1791-1867
Michael Faraday was an English physicist and chemist born in London. Faraday is thought by some to have been one of the greatest experimental scientists of all time, and was also a brilliant theorist. His theories on the nature of magnetism were later adopted by Maxwell, and played a part in Einstein's theory of relativity.
With only a basic education of reading and writing - and some very basic math skills he began his working life as an apprentice bookseller and binder. He took every opportunity to read, and came across an article on electricity in an encyclopedia. This stirred his interest in the subject, and he went on to create the science of electrochemistry.
A deeply religious man, much of his work seems to have been influenced by his belief in the divine harmony of the universe.
Faraday's Laws include the Law of Induction, Law of Electrolysis, and the Second Law of Electrolysis. The Farad - a unit of capacitance, is named after Faraday.
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David Sarnoff 1891-1971
Sarnoff was born in Russia, and moved to New York City as a boy. He worked as a telegraph operator in the Marconi company, and some accounts have him working at the key for three days straight during the Titanic disaster - although there is discussion of this being an exaggeration.
There is no doubt that Sarnoff was a driven man, and he was a great figure in the growth of broadcasting. Sarnoff became the general manager of RCA in 1921, and quickly became its vice-president. He saw the company through the rise of radio broadcasting, supervised the creation of the first network (NBC) and the move into television. During World War II he was a communications consultant, and for his service was named as a Brigadier General.
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Michael Idvorski Pupin 1858-1935
Michael Pupin was born in Hungary and came to the United States in 1874. He attended Columbia University and the University of Berlin. He was a professor of electromechanics at Columbia for 30 years, from 1901 to 1931. Pupin invented and improved upon many devices for telegraphy and telephony, including the use of inductors in telephone lines to improve the audio quality. His work with X-rays identified 'secondary radiation' - matter struck by X rays was stimulated to emit more X rays. He studied the behavior of vacuum tubes at low pressure, and invented an electrical resonator. A total of 34 patents were awarded for his inventions.
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Charles D. Herrold 1875-1948
Charles David Herrold was born in Illinois, and began his wireless work in San Jose, California. He was an inventor, teacher, and is thought by many to be the "Father of Broadcasting". 'Doc' Herrold was transmitting voice messages very early in the history of radio - as early as 1909 from the 'Herrold College of Wireless and Engineering' in San Jose. He had a regular schedule of transmitting between 1909 and 1917, and claimed to have coined the term 'Broadcasting'. In 1915, he broadcast to the Worlds Fair from 50 miles away, providing news and music. He patented the "Arc Fone" in 1915.
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Frank Conrad 1874-1941
Frank Conrad's amateur radio station 8XK, located in his garage in Wilkinsburg, Pennsylvania was one of the seeds from which broadcasting grew. 8XK was later licensed as KDKA. His early experience with radio included building sensitive receivers to hear the Naval Observatory time signals from Arlington, VA. Conrad left school in the 7th grade to work. He was transferred to the testing department at Westinghouse shortly after his employment in 1890. He became general engineer in 1904 and assistant chief engineer in 1921. He supervised the development of transmitting equipment, among other duties. He received an honorary degree of Doctor of Science from the University of Pittsburgh in 1928.
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Sir Joseph John Thomson 1856-1940
Born in Cheetham Hill, England, Joseph Thomson attended Cambridge University and maintained an association with Cambridge for most of his life. In 1906 he was awarded the Nobel Prize in Physics for his work on the conduction of electricity by gasses. His work with X-rays and cathode ray tubes convinced him that cathode rays were actually charged particles -electrons- and that their mass was roughly 1,000 times smaller than hydrogen ions.
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Just a personal comment on Edison's Fuse...
I wonder if you, like myself see the wonder of this discovery? I have no hard facts or information on Edison's invention of the fuse (If you have some, please let me know) - but I find it a testimony to his genius that he invented it. After so much work trying to create an electric light that would not burn out, and the thousands of failures at this, he took that failure and patented it as a useful invention. After all, his fuse was not much more than a light bulb designed to burn out at a specific current.
One of the things I keep hearing about Edison was how very practical he was. I think the invention of the fuse just about clinches it! What do you think? Amazing fellow, that Thomas Edison...
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Alexander Graham Bell 1847-1922
Bell was born in Scottland, and was home schooled until the age of ten. As a boy, his experiments with speech and sound reproduction led to a lifelong interest in the field.
He was granted a patent in 1874 on a method of sending two or more telegraphic messages on the same wire, at the same time. The next year, as a result of an accident, words to the effect of "Watson - come here, I want you" were reproduced electronically by his 'telephone'. In August of 1876 the distance spanned by telephone was 8 miles, and 'long distance' became a reality by the end of that year, as he communicated over 143 miles.
In 1880 Bell achieved the first wireless transmission of speech - using his invention -- the 'photophone' -- to transmit words on a beam of light.
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Samuel Finley Breese Morse 1791-1872
By the age of 21, Samuel Morse showed an interest in electrical experimentation. A shipboard conversation in 1832 planted the seed for a method of telegraphy, and by 1835 the basic physical elements of a relay system were in place. A patent was issued in 1840, and the U.S. Congress gave him a grant for $30,000 to construct a line between Washington and Baltimore. The first message on this line was sent on May 24th, 1844.
The "Morse Code" was invented by Morse, and his assistant Alfred Vail about 1840. The original code was simplified in 1851, and is called the 'Continental', or 'International' Morse code.
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