Reginald Fessenden
The Father of Radio Broadcasting
Born	October 6, 1866(1866-10-06) Bolton-Est, Quebec
Died	July 22, 1932 (aged 65) Bermuda
Occupation	Inventor and radio pioneer

Reginald Fessenden (October 6, 1866 РJuly 22, 1932) was a Canadian inventor, best known for his work in early radio. Three of his most notable achievements include: the first audio transmission by radio (1900), the first two-way transatlantic radio transmission (1906), and the first radio broadcast of entertainment and music (1906). public domain photo This image has been released into the public domain by the copyright holder, its copyright has expired, or it is ineligible for copyright. ... is the 279th day of the year (280th in leap years) in the Gregorian calendar. ... 1866 (MDCCCLXVI) is a common year starting on Monday of the Gregorian calendar or a common year starting on Wednesday of the 12-day-slower Julian calendar. ... Bolton-Est is a village of 700 people, part of the Memphr̩magog Regional County Municipality in the Estrie region of Quebec. ... is the 203rd day of the year (204th in leap years) in the Gregorian calendar. ... Year 1932 (MCMXXXII) was a leap year starting on Friday (the link will display full 1932 calendar) of the Gregorian calendar. ... For other uses, see Inventor (disambiguation). ... is the 279th day of the year (280th in leap years) in the Gregorian calendar. ... 1866 (MDCCCLXVI) is a common year starting on Monday of the Gregorian calendar or a common year starting on Wednesday of the 12-day-slower Julian calendar. ... is the 203rd day of the year (204th in leap years) in the Gregorian calendar. ... Year 1932 (MCMXXXII) was a leap year starting on Friday (the link will display full 1932 calendar) of the Gregorian calendar. ...

Early years

Reginald Aubrey Fessenden was born October 6, 1866, in East Bolton, Quebec, Canada, the eldest of Elisha Joseph and Clementina Trenholme Fessenden's four children. Elisha Fessenden was a priest of the Church of England in Canada, and through the years the family moved to a number of postings within the Province of Ontario. While growing up, Reginald was an accomplished student. In 1877, he attended Trinity College School in Port Hope, Ontario for two years, later, at the age of 14, he was granted a mathematics mastership to Bishop's College (now Bishop's University) in Lennoxville, Quebec. At the age of 18, Fessenden left Bishop's without having been awarded a degree, even though he had "done substantially all the work necessary". (This lack of a degree may have hurt Fessenden's employment opportunities—when McGill University established an electrical engineering department, Fessenden was turned down on an application to be the chairman, in favor of an American.) Bolton-Est is a village of 700 people, part of the Memphrémagog Regional County Municipality in the Estrie region of Quebec. ... , Motto: Je me souviens (French: I remember) Capital Quebec City Largest city Montreal Official languages French Government - Lieutenant-Governor Pierre Duchesne - Premier Jean Charest (PLQ) Federal representation in Canadian Parliament - House seats 75 - Senate seats 24 Confederation July 1, 1867 (1st) Area  Ranked 2nd - Total 1,542,056 km² (595... Clementina Trenholme, (4 May 1843 – 14 September 1918), was born at Trenholme, Canada East and died at Hamilton, Ontario. ... Anglican Church of Canada The Anglican Church of Canada (the ACC) is the Canadian branch of the Anglican Communion. ... For other institutions named Trinity School, see Trinity School. ... Port Hope is a municipality in Ontario, Canada, about 100 km east of Toronto and about 150 km west of Kingston filled with crack addicts. ... McGreer Building,1846 Bishops University is an English-language liberal arts university located in Sherbrooke, Quebec, Canada. ... SLennoxville, population 4,963 (2001), is a borough (Fr. ... McGill University is a publicly funded, co-educational research university located in the city of Montreal, Quebec, Canada. ...

The next two years he worked as the principal, and sole teacher, at the Whitney Institute in Bermuda. While there, he became engaged to Helen Trott—they married in September, 1890, and later had a son, Reginald Kennelly Fessenden.

Early work

Fessenden's classical education had provided him with only a limited amount of scientific and technical training. Interested in increasing his skills in the electrical field, he moved to New York City in 1886, with hopes of gaining employment with the famous inventor, Thomas Edison. As recounted in his 1925 Radio News autobiography, his initial attempts were rebuffed—in his first application, Fessenden wrote "Do not know anything about electricity, but can learn pretty quick", to which Edison replied "Have enough men now who do not know about electricity". However, Fessenden persevered, and before the end of the year was hired for a semi-skilled position as an assistant tester for the Edison Machine Works, which was laying underground electrical mains in New York City. He quickly proved his worth, and received a series of promotions, with increasing responsibility for the project. In late 1886, Fessenden began working directly for Edison at the inventor's new Laboratory at in West Orange, New Jersey. A broad range of projects included work in solving problems in chemistry, metallurgy, and electricity. However, in 1890, facing financial problems, Edison was forced to lay off most of the Laboratory employees, including Fessenden. “Edison” redirects here. ...

Taking advantage of his recent practical experience, Fessenden was able to find positions with a series of manufacturing companies. Next, in 1892, he received an appointment as professor for the newly formed Electrical Engineering department at Purdue University in West Lafayette, Indiana—while there he helped the Westinghouse Corporation install the lighting for the 1893 World Columbian Exposition in Chicago. Shortly thereafter, George Westinghouse personally recruited Fessenden for the newly created position of chair of the Electrical Engineering department at the Western University of Pennsylvania, the modern-day University of Pittsburgh. Purdue redirects here. ... One-third scale replica of The Republic, which once stood in the great basin at the exposition, Chicago, 2004 The World Columbian Exposition (also called The Chicago Worlds Fair), a Worlds fair, was held in Chicago in 1893 to celebrate the 400th anniversary of Christopher Columbuss discovery... Nickname: Motto: Urbs in Horto (Latin: City in a Garden), I Will Location in the Chicago metro area and Illinois Coordinates: , Country State Counties Cook, DuPage Settled 1770s Incorporated March 4, 1837 Government  - Mayor Richard M. Daley (D) Area  - City  234. ... This article does not cite any references or sources. ... The University of Pittsburgh, commonly referred to as Pitt, is a state-related, doctoral/research university in Pittsburgh, Pennsylvania, United States. ...

Radio work

In the late 1890s, reports began to appear about the success Guglielmo Marconi was having in developing a practical radio transmitting and receiving system. Fessenden began limited radio experimentation, and soon came to the conclusion that he could develop a far more efficient system than the spark-gap transmitter and coherer-receiver combination which had been championed by Oliver Lodge and Marconi. Guglielmo Marconi [gue:lmo marko:ni] (25 April 1874 - 20 July 1937) was an Italian inventor, best known for his development of a radiotelegraph system, which served as the foundation for the establishment of numerous affiliated companies worldwide. ... A typical spark transmitter circuit. ... The coherer was the first device used to detect radio signals in wireless telegraphy. ... Vanity Fair cartoon. ...

Weather Bureau contract and the first audio radio transmission

In 1900 Fessenden left the University of Pittsburgh to work for the United States Weather Bureau, with the objective of proving the practicality of using a network of coastal radio stations to transmit weather information, thus avoiding the need to use the existing telegraph lines. The contract gave the Weather Bureau access to any devices Fessenden invented, but he would retain ownership of his inventions. Fessenden quickly made major advances, especially in receiver design, as he worked to develop audio reception of signals. His initial success came from a barretter detector, which was followed by the electrolytic detector that consisted of a fine wire dipped in nitric acid, and for the next few years this later device would set the standard for sensitivity in radio reception. As his work progressed, Fessenden also evolved the heterodyne principle, which combined two signals to produce a third audible tone. However, heterodyne reception was not fully practical for a decade after it was invented, since it required a means for producing a stable local signal, which awaited the development of the oscillating vacuum-tube. The National Oceanic and Atmospheric Administration (NOAA) is an agency of the United States Department of Commerce. ... The Hot wire barretter was a demodulating detector invented in 1902 by Reginald Fessenden that found limited use in early radio receivers. ... The electrolytic detector or the bare-point electrolytic detector as it was also called, was a type of wet demodulator used in early radio receivers. ... In telecommunications, to heterodyne is to generate new frequencies by mixing two or more signals in a nonlinear device such as a vacuum tube, transistor, or diode mixer. ...

The initial work took place at Cobb Island, Maryland, located on the Potomac River about 80 kilometers (50 miles) downstream from Washington, DC. While there, Fessenden, experimenting with a high-frequency spark transmitter, successfully transmitted speech on December 23, 1900 over a distance of about 1.6 kilometers (one mile), which appears to have been the first audio radio transmission. At this time the sound quality was too distorted to be commercially practical, but as a test this did show that with further technical refinements it would become possible to transmit audio using radio signals.

As the experimentation expanded, additional stations were built along the Atlantic Coast in both North Carolina and Virginia. However, in the midst of promising advances, Fessenden became embroiled in disputes with his sponsor. In particular, he charged that Bureau Chief Willis Moore had attempted to gain a half-share of the patents — Fessenden refused to sign over the rights, and his work for the Weather Bureau ended in August, 1902. (This incident recalled F. O. J. Smith, a member of the House of Representatives from Maine, who had managed to gain a one-quarter interest in the Morse telegraph.)

Formation of NESCO

At this point, two wealthy Pittsburgh, Pennsylvania businessmen, Hay Walker, Jr., and Thomas H. Given, financed the formation of the National Electric Signaling Company (NESCO), to carry on Fessenden's research, including the development of both a high-power rotary-spark transmitter for long-distance radiotelegraph service, and a lower-powered continuous-wave alternator-transmitter, which could be used for both telegraphic and audio transmissions. Marshfield's Brant Rock, Massachusetts became the center of operations for the new company. Marshfield is a town in Plymouth County, Massachusetts, United States. ... Ocean Bluff and Brant Rock are villages located in the town of Marshfield in Plymouth County, Massachusetts. ... This article is about the U.S. State. ...

Rotary-spark transmitter and the first two-way transatlantic transmission

Photograph of Rotary Gap transmitter at Brant Rock, Ca 1906.

It was decided to try to establish a transatlantic radiotelegraph service, and, in January, 1906, employing his rotary-spark transmitters, Fessenden made the first successful two-way transatlantic transmission, exchanging Morse code messages between a station constructed at Brant Rock and an identical one built at Machrihanish in Scotland. (Marconi had only achieved one-way transmissions at this time.) However, the transmitters could not bridge this distance during daylight hours or in the summer, so work was suspended until later in the year. Then, on December 6, 1906, "owing to the carelessness of one of the contractors employed in shifting some of the supporting cables", the Machrihanish radio tower collapsed, abruptly ending the transatlantic work before it could ever go into commercial service. Image File history File links Size of this preview: 800 × 541 pixelsFull resolution (1318 × 892 pixel, file size: 125 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... Image File history File links Size of this preview: 800 × 541 pixelsFull resolution (1318 × 892 pixel, file size: 125 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ... 1922 Chart of the Morse Code Letters and Numerals Morse code is a method for transmitting telegraphic information, using standardized sequences of short and long elements to represent the letters, numerals, punctuation and special characters of a message. ... Machrihanish is a village in Scotland (Argyll and Bute). ... December 6 is the 340th day of the year (341st in leap years) in the Gregorian calendar. ... 1906 (MCMVI) was a common year starting on Monday (see link for calendar). ...

Postcard image, from around 1910, of the 128 meter (420 foot) tall Brant Rock radio tower.

Image File history File linksMetadata Download high-resolution version (513x800, 116 KB) Circa. ... Image File history File linksMetadata Download high-resolution version (513x800, 116 KB) Circa. ...

Alternator-transmitter and the first audio radio broadcast

The development of a rotary-spark transmitter was something of a stop-gap measure, to be used until a superior approach could be perfected. Fessenden felt that, ultimately, a continuous-wave transmitter—one that produced a pure sine-wave signal on a single frequency—would be far more efficient, particularly because it could be used for quality audio transmissions. His design idea was to take a basic electrical alternator, which normally operated at speeds that produced alternating current of at most a few hundred Hz, and greatly speed it up in order to create electrical currents at tens of kHz. Thus, the high-speed alternator would produce a steady radio signal when connected to an aerial. Then, by simply placing a carbon microphone in the transmission line, the strength of the signal could be varied in order to add sounds to the transmission—in other words, amplitude modulation would be used to impress audio on the radio frequency carrier wave. However, it would take many years of expensive development before even a prototype alternator-transmitter would be ready, and a few more years beyond that for high-power versions to become available. Hz or hz may mean: Herero language (ISO 639 alpha-2, hz) Hertz, unit of frequency This is a disambiguation page — a list of articles associated with the same title. ... Button microphone from Western Electric telephone. ... Amplitude modulation (AM) is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. ... It has been suggested that this article or section be merged with Radio waves. ... This article or section does not adequately cite its references or sources. ...

Fessenden contracted with General Electric to help design and produce a series of high-frequency alternator-transmitters. In 1903, Charles Proteus Steinmetz of GE delivered a 10 kHz version which proved of limited use and could not be directly used as a radio transmitter. Fessenden's request for a faster, more powerful unit was assigned to E. F. W. Alexanderson, and in August, 1906 he delivered an improved model which operated at a transmitting frequency of approximately 50 kHz, although with far less power than Fessenden's rotary-spark transmitters. Early 20th century Alternator made in Budapest, Hungary, in the power generating hall of a hydroelectric station. ... wtf Charles Proteus Steinmetz (April 9, 1865–October 26, 1923) was an American Mathematician and Electrical Engineer. ... Ernst Frederick Werner Alexanderson (January 25, 1878–May 14, 1975) was a Swedish-American electrical engineer. ...

The alternator-transmitter achieved the goal of transmitting quality audio signals, but the lack of any way to amplify the signals meant they were somewhat weak. On December 21, 1906, Fessenden made an extensive demonstration of the new alternator-transmitter at Brant Rock, showing its utility for point-to-point wireless telephony, including interconnecting his stations to the wire telephone network. (A detailed review of this demonstration appeared in the The American Telephone Journal.) ^[1] A few days later, two additional demonstrations took place, which appear to be the first audio radio broadcasts of entertainment and music ever made to a general audience. (Beginning in 1904, the U.S. Navy had broadcast daily time signals and weather reports, but these employed spark transmitters, transmitting in Morse code). On the evening of December 24, 1906 (Christmas Eve), Fessenden used the alternator-transmitter to send out a short program from Brant Rock, which included his playing the song O Holy Night on the violin and reading a passage from the Bible. On December 31, New Year's Eve, a second short program was broadcast. The main audience for both these transmissions was an unknown number of shipboard radio operators along the Atlantic Coast. Although now seen as a landmark, these two broadcasts were barely noticed at the time and soon forgotten—the only first-hand account appears to be a letter Fessenden wrote on January 29, 1932 to his former associate, Samuel M. Kinter. There are no known accounts in any ships radio logs, nor any contemporary literature, of the reported holiday demonstrations. In addition, Fessenden does not appear to have made any additional broadcasts intended for a general audience, and was actually promoting the alternator-transmitter as ideal for point-to-point wireless telephone service. Still, in retrospect, it was an important glimpse of the future of radio. (Although primarily designed for transmissions spanning a few kilometers, on a couple of occasions the test Brant Rock audio transmissions were apparently overheard by NESCO employee James C. Armor across the Atlantic at the Machrihanish site). is the 355th day of the year (356th in leap years) in the Gregorian calendar. ... 1906 (MCMVI) was a common year starting on Monday (see link for calendar). ... is the 358th day of the year (359th in leap years) in the Gregorian calendar. ... 1906 (MCMVI) was a common year starting on Monday (see link for calendar). ... The Christmas Eve (1904-05), watercolor painting by the Swedish painter Carl Larsson (1853-1919) Christmas Eve, the evening of December 24th, the preceding day or vigil before Christmas Day, is treated to a greater or a lesser extent in most Christian societies as part of the Christmas season. ... O Holy Night (Cantique de Noël) is a well-known Christmas carol composed by Adolphe Adam in 1847 to the French poem Minuit, chrétiens by Placide Cappeau (1808-1877), an accomplished amateur. ... is the 365th day of the year (366th in leap years) in the Gregorian calendar. ... New Years Eve is December 31, the final day of the Gregorian year, and the day before New Years Day. ... January 29 is the 29th day of the year in the Gregorian calendar. ... Year 1932 (MCMXXXII) was a leap year starting on Friday (the link will display full 1932 calendar) of the Gregorian calendar. ...

Continuing work and dismissal from NESCO

The technical achievements made by Fessenden were not matched by financial success. Walker and Given had hoped to sell NESCO to a larger company such as the American Telephone & Telegraph Company, but were unable to find a buyer. Fessenden's formation of the Fessenden Wireless Company of Canada in Montreal in 1906 may have led to suspicion that he was trying to freeze Walker and Given out of a potentially lucrative competing transatlantic service. There were growing strains between Fessenden and the company owners, and finally Fessenden was dismissed from NESCO in January of 1911. He in turn brought suit against NESCO for breach of contract. Fessenden won the initial court trial and was awarded damages, however, NESCO prevailed on appeal. To conserve assets, NESCO went into receivership in 1912, and Samuel Kintner was appointed general manager of the company—the legal stalemate would continue for over 15 years. In 1917, NESCO finally emerged from receivership, and was soon renamed the International Radio Telegraph Company. The company was sold to Westinghouse in 1920, and the next year its assets, including numerous important Fessenden patents, were sold to the Radio Corporation of America, which also inherited the Fessenden legal proceedings. Finally, on March 1, 1928, Fessenden settled his outstanding lawsuits with RCA, receiving a large cash payment. This article describes the former AT&T Corp. ... Nickname: Motto: Concordia Salus (well-being through harmony) Coordinates: , Country Province Founded 1642 Established 1832 Government  - Mayor Gérald Tremblay Area [1][2][3]  - City 365. ... RCA, formerly an initialism for the Radio Corporation of America, is now a trademark used by two companies for products descended from that common ancestor: Thomson Consumer Electronics, which manufactures RCA-branded televisions, DVD players, video cassette recorders, direct broadcast satellite decoders, camcorders, audio equipment, telephones, and related accessories; and...

Ongoing influence

After Fessenden left NESCO, E. F. W. Alexanderson continued to work on alternator-transmitter development at GE, mostly for long range radiotelegraph use. It took many years, but he eventually developed the high-powered Alexanderson alternator capable of transmitting across the Atlantic, and by 1916 the Fessenden-Alexanderson alternator was more reliable for transatlantic communication than spark apparatus. Also, after 1920, audio radio broadcasting became widespread, using vacuum-tube transmitters rather than the alternator, but employing the continuous-wave AM signals that Fessenden had helped introduce in 1906. In 1921, the Institute of Radio Engineers presented Fessenden with its Medal of Honor, and the next year the City of Philadelphia awarded him a John Scott Medal and a cash prize of $800 for his invention in "Continuous Wave Telegraphy and Telephony", and recognized him as "One whose labors had been of great benefit". Alexanderson Alternator in the Grimeton VLF transmitter. ... Following several attempts to form a technical organization of wireless practitioners in 1908-1912, the Institute of Radio Engineers (IRE) was finally established in 1912 in New York. ... Nickname: Motto: Philadelphia maneto - Let brotherly love endure Location in Pennsylvania Coordinates: , Country Commonwealth County Philadelphia Founded October 27, 1682 Incorporated October 25, 1701 Government  - Mayor John F. Street (D) Area  - City 369. ...

Later years

Although Fessenden ceased radio activities after his dismissal from NESCO in 1911, he continued to work in other fields. As early as 1904 he had helped engineer the Niagara Falls power plant for the newly formed Hydro-Electric Power Commission of Ontario. However, his most extensive work was in developing a type of sonar system for submarines to signal each other, as well as a method for locating icebergs, to help avoid another disaster like the one that sank Titanic. At the outbreak of World War I, Fessenden volunteered his services to the Canadian government and was sent to London, England where he developed a device to detect enemy artillery and another to locate enemy submarines. For other uses, see Niagara Falls (disambiguation). ... The Hydro-Electric Power Commission of Ontario was established in 1906 by the provincial Power Commission Act to build transmission lines to supply municipal utilities with electricity generated by private companies already operating at Niagara Falls. ... For other uses, see Titanic (disambiguation). ... “The Great War ” redirects here. ... London — containing the City of London — is the capital of the United Kingdom and of England and a major world city. With over seven million inhabitants (Londoners) in Greater London area, it is amongst the most densely populated areas in Western Europe. ...

An inveterate tinkerer, Fessenden eventually became the holder of more than 500 patents He could often be found in a river or lake, floating on his back, a cigar sticking out of his mouth and a hat pulled down over his eyes. At home he liked to lie on the carpet, a cat on his chest. In this state of relaxation, Fessenden could imagine, invent and think his way to new ideas, including a version of microfilm, that helped him to keep a compact record of his inventions, projects and patents. He patented the basic ideas leading to reflection seismology, a technique important for its use in exploring for petroleum. In 1915 he invented the fathometer, a sonar device used to determine the depth of water for a submerged object by means of sound waves, for which he won Scientific American's Gold Medal in 1929. Microfilm machines may be available at libraries or record archives. ... Seismic reflection data Reflection seismology (or seismic reflection) is a method of exploration geophysics that uses the principles of seismology to estimate the properties of the Earths subsurface from reflected seismic waves. ... Pumpjack pumping an oil well near Lubbock, Texas Ignacy Łukasiewicz - inventor of the refining of kerosene from crude oil. ... Cabin display of a commercial or oceanographic fathometer sonar A fishfinder is a type of Fathometer, both being specialized types of echo sounding systems, a type of Active SONAR. (Sounding is the measurement of water depth, a historical nautical term of very long usage. ... This article is about underwater sound propagation. ... Scientific American is a popular-science magazine, published (first weekly and later monthly) since August 28, 1845, making it the oldest continuously published magazine in the United States. ...

Death and afterwards

Although Fessenden's antenna in Brant Rock, Massachusetts was demolished in 1917, the insulated base on which it stood still survives. The layers of concrete were originally separated by arrays of ceramic insulators.

After settling his lawsuit with RCA, Fessenden purchased a small estate called "Wistowe" in Bermuda. He died there in 1932 and was interred in the cemetery of St Mark's Church on the island. An editorial in the New York Herald Tribune said: Image File history File linksMetadata Download high-resolution version (3456x2304, 4438 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Reginald Fessenden Metadata This file contains additional information, probably added from the digital camera or scanner used to... Image File history File linksMetadata Download high-resolution version (3456x2304, 4438 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Reginald Fessenden Metadata This file contains additional information, probably added from the digital camera or scanner used to... Ocean Bluff and Brant Rock are villages located in the town of Marshfield in Plymouth County, Massachusetts. ... The New York Herald Tribune was a newspaper created in 1924 when the New York Tribune acquired the New York Herald. ...

It sometimes happens, even in science, that one man can be right against the world. Professor Fessenden was that man. He fought bitterly and alone to prove his theories. It was he who insisted, against the stormy protests of every recognized authority, that what we now call radio was worked by continuous waves sent through the ether by the transmitting station as light waves are sent out by a flame. Marconi and others insisted that what was happening was a whiplash effect. The progress of radio was retarded a decade by this error. The whiplash theory passed gradually from the minds of men and was replaced by the continuous wave — one with all too little credit to the man who had been right.

Fessenden's private residence at 45 Waban Hill Road in the Chestnut Hill district of Newton, Massachusetts is on the National Register of Historic Places. The Reginald A. Fessenden House, 45 Waban Hill Road in the village of Chestnut Hill in Newton, Massachusetts, was the residence from 1919 to 1932 of the inventor,Reginald A. Fessenden, called the Father of Radio Broadcasting, because he was the first to broadcast the human voice and music by... Boston College and the Chestnut Hill Reservoir Located 6 miles west of Boston, Chestnut Hill is a wealthy suburb notable for its stately old houses, scenic landscape and the historic campus of Boston College. ... Nickname: Location in Middlesex County in Massachusetts Coordinates: , Country State County Middlesex County Settled 1630 Incorporated 1688 Government  - Type Mayor-council city  - Mayor David B. Cohen (Dem) Area  - City  18. ... A typical plaque showing entry on the National Register of Historic Places. ...

Quotations

An inventor is one who can see the applicability of means to supplying demand five years before it is obvious to those skilled in the art.

"The Inventions of Reginald A. Fessenden". (January, 1925). Radio News, p. 1142.

Patents

viewing these patent images requires TIFF capable software

• U.S. Patent 644,972 , "Induction Coil for X-ray Apparatus" – March, 1900
• U.S. Patent 648,660 , "X-ray Apparatus" – May, 1900
• U.S. Patent 654,390 , "Induction-coil" – July, 1900
• U.S. Patent 706,740 , "Wireless Signaling" (heterodyne principle) – August, 1902
• U.S. Patent 706,741 , "Apparatus for Wireless Telegraphy" (compressed air spark gap transmitter) – August, 1902
• U.S. Patent 706,742 , "Wireless Signaling", August, 1902 (transmit-receive switch)
• U.S. Patent 706,744 , "Current Actuated Wave Responsive Device" ("barretter" detector) – August, 1902
• U.S. Patent 706,745 , "Signaling by Electromagnetic Waves" – issued August 1902
• U.S. Patent 706,746 , "Signaling by Electromagnetic Waves" (ground plane) – issued August 1902
• U.S. Patent 706,747 , "Apparatus for Signaling by Electromagnetic Waves" (voice modulation of 50 kHz alternator – continuous wave transmitter) – August, 1902
• U.S. Patent 715,203 , "Selective Signaling by Electromagnetic Waves" (multiplex transmission and reception) – December, 1902
• U.S. Patent 727,327 , "Receiver for Electromagnetic Waves" – May, 1903
• U.S. Patent 727,328 , "Receiver for Signaling" – May, 1903
• U.S. Patent 727,329 , "Signaling by Electromagnetic Waves" – May, 1903
• U.S. Patent 727,330 , "Signaling by Electromagnetic Waves" – May, 1903
• U.S. Patent 727,331 , "Receiver for Electromagnetic Waves" (improved "barretter" -- actually electrolytic detector) – May, 1903
• U.S. Patent 793,648 , "Receiver for Electromagnetic Waves" (sealed/pressurized electrolytic detector) – December, 1904
• U.S. Patent 948,068 , "Wireless Telegraphy" (antenna tuning) – 1st February 1910
• U.S. Patent 974,762 , "Improvements in Wireless Telegraphy" – 1st November 1910
• U.S. Patent 1,059,665 , "Wireless Telegraphy" (antenna tuning)– issued April 1913
• U.S. Patent 1,108,895 , "Signaling by Sound and Other Longitudinal Elastic Impulses" – September, 1914
• U.S. Patent 1,147,010 , "Improvements in Wireless Telegraphy" – 20th July 1915
• U.S. Patent 1,576,735 , "Infusor" (for making tea) – March, 1926

This article is about TIFF, the computer image format. ... In telecommunications, to heterodyne is to generate new frequencies by mixing two or more signals in a nonlinear device such as a vacuum tube, transistor, or diode mixer. ... The spark gap transmitter was the first practical way to send radio signals. ... In telecommunication, a ground plane is an electrically conductive surface that serves as the near-field reflection point for an antenna, or as a reference ground in a circuit. ...

Reissued

• U.S. Patent RE12,115  "Receiver for Electromagnetic Waves" – duplicate of 727331 reissued May, 1903

See also

• Alexanderson alternator : used by Fessenden for his first radio broadcast.
• Fessenden transducer

Alexanderson Alternator in the Grimeton VLF transmitter. ... This article is about underwater sound propagation. ...

Further reading

• Hugh G. J. Aitken, The Continuous Wave: Technology and American Radio, 1900-1932. Princeton University Press. Princeton, New Jersey. 1985.
• Susan J. Douglas, Inventing American Broadcasting, 1899-1922. The Johns Hopkins University Press. Baltimore, Maryland. 1987.
• Orrin E. Dunlap, Jr., Radio's 100 Men of Science, Reginald Aubrey Fessenden entry, p. 137-141. Harper & Brothers Publishers. New York. 1944.
• Helen M. Fessenden, Fessenden: Builder of Tomorrows. Coward-McCann, Inc. New York. 1940.
• Reginald A. Fessenden, "The Inventions of Reginald A. Fessenden". Radio News, 11 part series beginning with the January, 1925 issue.
• Reginald A. Fessenden, "Wireless Telephony." Pp. 553-629. Transactions of the American Institute of Electrical Engineers: January 1 to June 30, 1908. Vol. XXVII, Part I. New York. 1908.
• S. M. Kinter, "Pittsburgh's Contributions to Radio." Pp. 1849-1862. Proceedings of the Institute of Radio Engineers. December, 1932.
• David W. Kraeuter, "The U. S. Patents of Reginald A. Fessenden". Pittsburgh Antique Radio Society, Inc., Washington Pennsylvania. 1990. OCLC record 20785626
• Ormond Raby, Radio's First Voice, Macmillan Company of Canada Limited, 1970

External links

• Fessenden - 100 Years of Radio
• Belrose, John S., "Fessenden and Marconi: Their Differing Technologies and Transatlantic Experiments During the First Decade of this Century" International Conference on 100 Years of Radio (September 5-7, 1995).
• Grant, John, "Experiments and Results in Wireless Telephony" The American Telephone Journal, January 26, 1907
• O'Neal, James E. "Fessenden: World's First Broadcaster?--A Radio History Buff Finds That Evidence for the Famous Brant Rock Broadcast Is Lacking" Radio World Online. October 25, 2006
• Seitz, Frederick, "The Cosmic Inventor" Transactions of the American Philosophical Society. 1999.
• George H. Clark Radioana Collection, ca. 1880 - 1950 - National Museum of American History, Smithsonian Institution.
• Reginald Fessenden web page
• Radio Machrihanish, Scotland - partner station to Brant Rock
• The National Electric Signaling Co. The New England Wireless and Steam Museum
• "Christmas Eve and the Birth of 'Talk' Radio" NPR All Things Considered, December 22, 2006
• Storied broadcast in doubt
• Biography and photos at the Canada's Telecommunications Hall of Fame website
• Biographical video footage at the Canada's Telecommunications Hall of Fame website