Ernst Frederick Werner Alexanderson (January 25, 1878–May 14, 1975) was a Swedish-American electrical engineer. Born in Uppsala, Sweden, and educated at the Royal Institute of Technology in Stockholm and the Technische Hochschule (Technical University) in Berlin, Germany, he spent his professional life in the US. He emigrated to the U.S. in 1902 and spent much of his life working for the General Electric company. He designed the Alexanderson alternator, a high-frequency generator for longwave transmissions, which made modulated (voice) radio broadcasts practical. The only surviving transmitter in a working state is at the Grimeton radio station outside Varberg, Sweden. It is a prime example of pre-electronic radio technology and was added to UNESCO's World heritage list in 2004. January 25 is the 25th day of the year in the Gregorian calendar. ... 1878 (MDCCCLXXVIII) was a common year starting on Tuesday (see link for calendar). ... May 14 is the 134th day of the year in the Gregorian Calendar (135th in leap years). ... 1975 (MCMLXXV) was a common year starting on Wednesday. ... Children from Lapland at the Ellis Island Immigration Station, N.Y. and N.J., USA, photographed c. ... An engineers degree is an academic degree which is intermediate in rank between a masters degree and a doctorate; it is occasionally to be encountered in the United States in technical fields. ... This article is about the modern city of Uppsala. ... The Royal Institute of Technology or Kungliga tekniska högskolan (KTH) is a university in Stockholm, Sweden. ...   (IPA: ; UN/LOCODE: SE STO) is the capital of Sweden, and consequently the site of its Government and Parliament as well as the residence of the Swedish head of state, King Carl XVI Gustaf. ... Technische Hochschule (acronym TH) is, what a university of technology (i. ... A University of Technology is an university with a focus on technology. ... For other uses, see Berlin (disambiguation). ... For other uses, see United States (disambiguation) and US (disambiguation). ... GE redirects here. ... An Alexanderson alternator is a rotating machine for the generation of high frequency with frequencies until 100 kHz. ... VLF transmitter Grimeton The VLF transmitter Grimeton is a VLF transmission facility near Grimeton close to Varberg in Sweden. ... Coordinates: Country Sweden County Halland County Province Halland Charter 1100 Area    - City km² Population    - City (2006) 25,000 Time zone CET (UTC+1) CEST (UTC+2) Website: www2. ... UNESCO logo UNESCO (United Nations Educational, Scientific and Cultural Organization) is a specialized agency of the United Nations established in 1945. ... Elabana Falls is in Lamington National Park, part of the Central Eastern Rainforest Reserves World Heritage site in Queensland, Australia. ...

He had been employed at General Electric for only a short period of time when GE received an order from Canadian-born professor and researcher Reginald Fessenden for an alternator with 1000 times higher frequency than any in existence at that time. In the summer of 1906 Dr. Alexanderson presented a 50 kHz alternator that was installed in Fessenden's radio station in Brant Rock, Massachusetts. By fall its output had been improved to 500 watts and 75 kHz. On Christmas Eve, 1906, Fessenden broadcast the first radio transmission with music and talk, playing the violin and reading the gospel himself. The transmission was heard as far away as the Caribbean Sea. GE redirects here. ... Reginald Aubrey Fessenden (October 6, 1866 – July 22, 1932) was a Canadian-born inventor, best known for his work in early radio. ... A kilohertz (kHz) is a unit of frequency equal to 1,000 hertz (1,000 cycles per second). ... Ocean Bluff and Brant Rock are villages located in the town of Marshfield in Plymouth County, Massachusetts. ... Map of Central America and the Caribbean A Caribbean beach in Isla Margarita, Venezuela. ...

Dr. Alexanderson was also instrumental in the development of television. The first television broadcast in the United States was to his GE Plot home at 1132 Adams Rd in 1927. Over his lifetime, Dr. Alexanderson received 345 patents, the last awarded in 1973 at age 94. The inventor and engineer remained active to an advanced age, working as a consultant to GE and RCA in the 1950's . He is buried at Vale Cemetery in Schenectady, New York. RCAs logo as seen today on many products. ... 1950 (MCML) was a common year starting on Sunday (link will take you to calendar). ... Vale Cemetery is a cemetery in Schenectady, New York. ... Schenectady is a city located in Schenectady County, New York, of which it is the county seat. ... NY redirects here. ...

In 1983, he was inducted into the National Inventors Hall of Fame. 1983 (MCMLXXXIII) was a common year starting on Saturday of the Gregorian calendar. ... The National Inventors Hall of Fame is an organization that honors important inventors from the United States. ...

Patents

• U.S. Patent 1008577  – High frequency alternator (100 kHz), filed April, 1909; issued, November, 1911
• U.S. Patent 1173079  – Selective Tuning System (Tuned RF Circuit, filed October, 1913; issued February, 1916
• U.S. Patent 1723908  – Ignition system, (RFI suppressor), filed June, 1926; issued August, 1929
• U.S. Patent 1775801  – Radio signaling system (directional antenna), filed November 1927, issued September 1930

A kilohertz (kHz) is a unit of frequency equal to 1,000 hertz (1,000 cycles per second). ... The Tuned Radio Frequency Receiver (short TRF) was invented by Edwin Armstrong in 1918. ... Radio Frequency Interference (RFI) is electromagnetic radiation which is emitted by electrical circuits carrying rapidly changing signals, as a by-product of their normal operation, and which causes unwanted signals (interference or noise) to be induced in other circuits. ...

See also

Tuned radio frequency receiver The Tuned Radio Frequency Receiver (short TRF) was invented by Edwin Armstrong in 1918. ...

References

• David E. Fisher and Marshall J. Fisher, Tube, the Invention of Television Counterpoint, Washington D.C. USA, (1996) ISBN 1-887178-17-1
• E.F.W. Alexanderson. General Electric Review, January, 1913
• E.F.W. Alexanderson, "Transatlantic Radio Communication", Trans. AIEE, (1919), pp. 1077-1093

External links

• Inventor's Hall of Fame citation accessed April 10, 2006
• Biography at IEEE History Center accessed April 10, 2006
• Biography at Oldradio.com accessed April 10, 2006
• Illustrated biography at prof. Eugenii Katz website accessed April 10, 2006
• Fessenden and Marconi – their technologies and transatlantic experiments compared. Accessed April 10, 2006
• Transoceanic Radio Communication in 1920, by E.F.W. Alexanderson accessed April 10, 2006
• "A Historical Review of Continuous Wave Radio Frequency Power Generators" accessed April 10, 2006