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A Short History of Radio

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A Short History of Radio Winter 2003-2004 AA ShortShort HistoryHistory ofof RadioRadio With an Inside Focus on Mobile Radio PIONEERS OF RADIO If success has many fathers, then radio • Edwin Armstrong—this WWI Army officer, Columbia is one of the world’s greatest University engineering professor, and creator of FM radio successes. Perhaps one simple way to sort out this invented the regenerative circuit, the first amplifying re- multiple parentage is to place those who have been ceiver and reliable continuous-wave transmitter; and the given credit for “fathering” superheterodyne circuit, a means of receiving, converting radio into groups. and amplifying weak, high-frequency electromagnetic waves. His inventions are considered by many to provide the foundation for cellular The Scientists: phones. • Henirich Hertz—this Clockwise from German physicist, who died of blood poisoning at bottom-Ernst age 37, was the first to Alexanderson prove that you could (1878-1975), transmit and receive Reginald Fessin- electric waves wirelessly. den (1866-1932), Although Hertz originally Heinrich Hertz thought his work had no (1857-1894), practical use, today it is Edwin Armstrong recognized as the fundamental (1890-1954), Lee building block of radio and every DeForest (1873- frequency measurement is named 1961), and Nikola after him (the Hertz). Tesla (1856-1943). • Nikola Tesla—was a Serbian- Center color American inventor who discovered photo is Gug- the basis for most alternating-current lielmo Marconi machinery. In 1884, a year after (1874-1937). coming to the United States he sold The Businessmen: the patent rights for his system of alternating- current dynamos, transformers, and motors to George • Guglielmo Marconi—this Italian crea- Westinghouse. He then established his own lab where he tor spent most of his working life in invented, among other things, the Tesla coil, an induction England where he introduced many of coil widely used in radio. the first uses of wireless telegraphy to European navies. His radio apparatus is • Ernst Alexanderson—born in Sweden, this remarkable widely considered to be the reason that inventor developed the first alternator to make over 700 people survived the Titanic disaster in 1912— transmission of speech (as opposed to the dots and dashes instead of dying as they likely would have if ships at sea of telegraphs) possible. It is said that this holder of 344 were still using carrier pigeons to communicate over great patents “virtually invented everything General Electric did distances. in the field of AM, FM, and TV.” • Lee DeForest—credited with being the “father of Ameri- • Reginald Fessenden—this Canadian spent much of his can radio.” DeForest was a direct competitor to Marconi at working life in the U.S. where he developed a way to the turn of the century (1899), when he was the chief scien- combine sound and radio carrier waves. His first effort to tist at the U.S.’s first radio firm—American Wireless Tele- transmit this mixed signal— to a receiver where the phone and Telegraph—until Marconi took over the com- carrier wave would be removed and the listener could hear pany’s assets in 1912 after a series of financial scandals. the original sound— failed. However, in 1906, using Although he held 300 patents, DeForest’s greatest techno- Alexanderson’s Alternator, Fessenden made the first long- logical contribution is considered to be his 1906 “Audion” range transmission of voice from Brant Rock, MA. vacuum tube. Inside Focus on Mobile Radio Page 2 MOBILE RADIO AT WORK GENERAL RADIO here are hundreds, if not thousands, of uses of radio Detroit police radio car TIMELINE spectrum and technology. Everything from baby moni- with antennas running tors and broadcasting to radar and radio beacons are across the roof (1921). Heinrich Hertz proved applications of radio. These two pages focus on the that electricity can be T first historical use of radio—mobile radio. transmitted in electro- 1885 magnetic waves. He conducted experi- Robert Loraine was the But mobile radio isn’t just ments in sending and second pilot to demon- for safety purposes today. receiving these waves strate wireless transmis- during the late 1880s. sion from a Taxi drivers, tow truck plane (1910). dispatchers, Radios (what we’d call wireless tele- Technologies graphs today) began to 1891 appear on ships at sea. that underpin This reduced the isola- mobile radio were tion of the ships thus first put to work in improving both reli- the 1890s on ability and safety. behalf of ocean- Nikola Tesla wire- going ships, which 1892 lessly transmitted had previously to electromagnetic en- relied on carrier 1893 ergy. He made the first public demonstra- pigeons and flags tion of radio in St. for their Louis in 1893. communications. Guglielmo Marconi filed for patent protec- In 1910, Frederick 1896 tion of his radio appa- Baldwin and John to ratus. He established 1897 the Wireless Tele- McCurdy were graph and Signal the first to trail Company in 1897. an aerial behind their bi-plane to The R.F. Matthews demonstrate was the first ship to 1899 request emergency radio’s uses for assistance using a aviation. wireless apparatus (Marconi’s system). In 1921, Detroit First transAtlantic police The Titanic, showing its 1901 signal sent-by Mar- commissioner radio antennas strung from coni from Ireland to William bow to stern (1912). Canada. Rutledge was Amateur (today the first public safety and package delivery ser- ing efficient and effective known as “ham”) official to use radio vices are just a few of the use of the radio spectrum by radio introduced to the business, while guaranteeing U.S. via a Scientific equipped vehicles. businesses that make inno- the reliability and inter- 1902 American article on vative use of mobile radio. “How to Construct an operability of all public Today, maritime, aviation, Efficient Wireless safety radio uses. Telegraphy Apparatus and land-based mobile radio In fact, mobile radio has at Small Cost.” systems remain among the become such a key tool in In finding a way to make this most important non- all business communica- all work, the FCC helps broadcast uses of the tions that one of the FCC’s make America a safer and ...Continued on last page... radio spectrum. major challenges is ensur- better place to live. Inside Focus on Mobile Radio Page 3 CELL PHONES—ONE OF TODAY’S MOST POPULAR USES OF MOBILE RADIO Cellular phones, including Personal Communication The year after the FCC made its final 1982 decision on Service devices, may seem like one of the newest spectrum for cellular systems, Ameritech Mobile land mobile services, but the idea of a mobile radio Communications (Chicago) and CellularOne telephone has been around for quite a while. (Washington, D.C.) became the first operational commercial cellular providers in the United States. In the early 1920s both the Marconi company and the Bell Laboratories were testing car-based telephone Personal communications for people on–the-go, not just systems. Bell Labs believes its 1924 system was those in vehicles, evolved further in the 1990s and actually the first two-way, voice-based radio continues growing today. telephone. Other predecessors to today’s cell phones included the radio telephones used by the military during both World Wars. The science behind cell phones, as we know them today, was clearly known by 1945 as evidenced by a Saturday Evening Post article, “Phone Me by Air,” which quoted FCC Commissioner E.K. Jett on frequency reuse for “small zone systems.” He said, “In each zone, the…frequencies will provide from 70 to 100 different channels, half of which may be used simultaneously in the same area without overlapping.” Although not yet a cellular system, in 1946 Bell initiated America’s first commercial mobile radio telephone system. Bell, as well as Ericsson, Nokia, and Motorola then went on to develop cell phone technologies throughout the 1950s and 1960s. The FCC approved a major Clockwise from top right—a WWI mobile military allocation of spectrum for mobile radio systems in phone, of the type Edwin Armstrong used to develop his ground-breaking inventions; Marconi’s 1922 car phone system with receivers, amplifiers, and 1970. In 1973, Motorola’s Martin Cooper was speakers mounted on the running boards; Martin Cooper with his 1973 cellular credited with the invention of the first personal, telephone; older and newer generations of mobile radio telephones; and Bell handheld cellular radio telephone. Labs’ 1924 test of a mobile radio telephone. Page 4 A Short History of Radio TIMELINE WHERE TO LEARN MORE Reginald Fessenden is the 1st to transmit1948 a program of 1906 Find out more about the history and technology of radio by visiting any of the fol- speech and music. lowing sites: • Early Radio History—http://earlyradiohistory.us Lee DeForest produces the “Audion,” a triode vacuum 1906 • Engineering history—http://www.ieee.org/organizations/history_center/ tube that allowed for ampli- • Electromagnetic spectrum— fication of radio signals. http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html • Radio History Society—http://www.radiohistory.org/ First radio transmission 1910 • Surfing the Aether—http://www.northwinds.net/bchris/ from an airplane. • Marconi Calling—http://www.marconicalling.com/front.htm • Edwin Armstrong—http://users.erols.com/oldradio/index.htm Federal regulation of American airwaves begins. • Mobile Telephone History—http://www.privateline.com/index.html Amateurs had to be li- 1912 • Mobile Services— censed; ships had to have a http://www.ntia.doc.gov/openness/sp_rqmnts/mobile1.html radio and trained operators. • FCC Regulation of Wireless Services—http://wireless.fcc.gov/services/ All U.S. radio stations not needed by the government 1917 are closed as WWI begins. WIRELESS—ONE WORD, MANY Edwin Armstrong patented the Super Heterodyne Re- MEANINGS ceiver based on work he 1918 While a rose may smell the same regardless of what it’s called, the term “wireless” did as an officer in the has referred to distinctly different things throughout the past century.
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