History of radio

The early history of radio is the

In an 1864 presentation, published in 1865,

After their discovery many scientists and inventors experimented with transmitting and detecting "Hertzian waves" (it would take almost 20 years for the term "radio" to be universally adopted for this type of electromagnetic radiation).^[8] Maxwell's theory showing that light and Hertzian electromagnetic waves were the same phenomenon at different wavelengths led "Maxwellian" scientists such as John Perry, Frederick Thomas Trouton and Alexander Trotter to assume they would be analogous to optical light.^[9][10]

Following Hertz' untimely death in 1894, British physicist and writer

After Lodge's demonstrations researchers pushed their experiments further down the electromagnetic spectrum towards visible light to further explore the

Between 1890 and 1892 physicists such as John Perry, Frederick Thomas Trouton and William Crookes proposed electromagnetic or Hertzian waves as a navigation aid or means of communication, with Crookes writing on the possibilities of wireless telegraphy based on Hertzian waves in 1892.^[18] Among physicist, what were perceived as technical limitations to using these new waves, such as delicate equipment, the need for large amounts of power to transmit over limited ranges, and its similarity to already existent optical light transmitting devices, lead them to a belief that applications were very limited. The Serbian American engineer Nikola Tesla considered Hertzian waves relatively useless for long range transmission since "light" could not transmit further than line of sight.^[19] There was speculation that this fog and stormy weather penetrating "invisible light" could be used in maritime applications such as lighthouses,^[18] including the London journal The Electrician (December 1895) commenting on Bose's achievements, saying "we may in time see the whole system of coast lighting throughout the navigable world revolutionized by an Indian Bengali scientist working single handed[ly] in our Presidency College Laboratory."^[20]

In 1895, adapting the techniques presented in Lodge's published lectures, Russian physicist

In 1894, the young Italian inventor

In 1897, Marconi established a radio station on the Isle of Wight, England and opened his "wireless" factory in the former silk-works at Hall Street, Chelmsford, England, in 1898, employing around 60 people.

On 12 December 1901, using a 500-foot (150 m) kite-supported antenna for reception—signals transmitted by the company's new high-power station at

Marconi began to build high-powered stations on both sides of the Atlantic to communicate with ships at sea. In 1904, he established a commercial service to transmit nightly news summaries to subscribing ships, which could incorporate them into their on-board newspapers. A regular transatlantic radio-telegraph service was finally begun on 17 October 1907[33]^[34] between Clifden, Ireland, and Glace Bay, but even after this the company struggled for many years to provide reliable communication to others.

Marconi's apparatus is also credited with saving the 700 people who survived the tragic Titanic disaster.^[35]

Audio transmission

In the late 1890s, Canadian-American inventor

The Dutch company Nederlandsche Radio-Industrie and its owner-engineer, Hanso Idzerda, made its first regular entertainment radio broadcast over station PCGG from its workshop in The Hague on 6 November 1919. The company manufactured both transmitters and receivers. Its popular program was broadcast four nights per week using narrow-band FM transmissions on 670 metres (448 kHz),^[48] until 1924 when the company ran into financial trouble.

Regular entertainment broadcasts began in Argentina, pioneered by Enrique Telémaco Susini and his associates. At 9 pm on August 27, 1920, Sociedad Radio Argentina aired a live performance of Richard Wagner's opera Parsifal from the Coliseo Theater in downtown Buenos Aires. Only about twenty homes in the city had receivers to tune in this program.

On 31 August 1920 the

As equipment progressed, precise frequency control became possible; early stations often did not have a precise frequency, as it was affected by the temperature of the equipment, among other factors. Identifying a radio signal by its frequency rather than its length proved much more practical and useful, and starting in the 1920s this became the usual method of identifying a signal, especially in the United States. Frequencies specified in number of cycles per second (kilocycles, megacycles) were replaced by the more specific designation of hertz (cycles per second) about 1965.

Radio companies

British Marconi

Using various

The invention of amplitude-modulated (AM) radio, which allows more closely spaced stations to simultaneously send signals (as opposed to spark-gap radio, where each transmission occupies a wide bandwidth) is attributed to Reginald Fessenden, Valdemar Poulsen and Lee de Forest.

Crystal set receivers

The most common type of receiver before vacuum tubes was the

The art and science of crystal sets is still pursued as a hobby in the form of simple un-amplified radios that 'runs on nothing, forever'. They are used as a teaching tool by groups such as the Boy Scouts of America to introduce youngsters to electronics and radio. As the only energy available is that gathered by the antenna system, loudness is necessarily limited.

Vacuum tubes

During the mid-1920s, amplifying vacuum tubes revolutionized radio receivers and transmitters. John Ambrose Fleming developed a vacuum tube diode. Lee de Forest placed a screen, added a "grid" electrode, creating the triode.^[55]

Early radios ran the entire power of the transmitter through a

In 1929 a new screen grid tube called UY-224 was introduced, an amplifier designed to operate directly on alternating current.[57]

A problem with the early radios was fading stations and fluctuating volume. The invention of the superheterodyne receiver solved this problem, and the first radios with a heterodyne radio receiver went for sale in 1924. But it was costly, and the technology was shelved while waiting for the technology to mature, and in 1929 the Radiola 66 and Radiola 67 went for sale.^[58][59][60]

Loudspeakers

In the early days one had to use headphones to listen to radio. Later loudspeakers in the form of a horn of the type used by phonographs, equipped with a telephone receiver, became available. But the sound quality was poor. In 1926 the first radios with electrodynamic loudspeakers went for sale, which improved the quality a lot. At first the loudspeakers were separated from the radio, but soon radios would come with a built-in loudspeaker.^[61]

Other inventions related to sound was the automatic volume control (AVC), first commercially available in 1928.^[62] In 1930 a tone control knob was added to the radios. This allowed listeners to improve imperfect broadcasting.^[63]

The magnetic cartridge, which was introduced in the mid 20's, greatly improved the broadcasting of music. When playing music from a phonograph before the magnetic cardridge, a microphone had to be placed close to a horn loudspeaker. The invention allowed the electric signals to be amplified and then fed directly to the broadcast transmitter.^[64]

Transistor technology

Following development of transistor technology, bipolar junction transistors led to the development of the transistor radio. In 1954, the Regency company introduced a pocket transistor radio, the TR-1, powered by a "standard 22.5 V Battery." In 1955, the newly formed Sony company introduced its first transistorized radio, the TR-55.^[65] It was small enough to fit in a vest pocket, powered by a small battery. It was durable, because it had no vacuum tubes to burn out. In 1957, Sony introduced the TR-63, the first mass-produced transistor radio, leading to the mass-market penetration of transistor radios.^[66] Over the next 20 years, transistors replaced tubes almost completely except for high-power transmitters.

By the mid-1960s, the

The first integrated circuit (IC) radio, P1740 by General Electric, became available in 1966.^[69]

Car radio

The first car radio was introduced in 1922, but it was so large that it took up too much space in the car.^[70] The first commercial car radio that could easily be installed in most cars went for sale in 1930.^[71][72]

Radio telex

One of the first developments in the early 20th century was that aircraft used commercial AM radio stations for navigation, AM stations are still marked on U.S. aviation charts. Radio navigation played an important role during war time, especially in World War II. Before the discovery of the crystal oscillator, radio navigation had many limits.^[73] However, as radio technology expanding, navigation is easier to use, and it provides a better position. Although there are many advantages, the radio navigation systems often comes with complex equipment such as the radio compass receiver, compass indicator, or the radar plan position indicator. All of these require users to obtain certain knowledge.

In the 1960s

In the 1930s, regular analog television broadcasting began in some parts of Europe and North America. By the end of the decade there were roughly 25,000 all-electronic television receivers in existence worldwide, the majority of them in the UK. In the US, Armstrong's FM system was designated by the FCC to transmit and receive television sound.

Color television

• 1953: NTSC compatible color television introduced in the US.
• 1962: Telstar 1, the first communications satellite, relayed the first publicly available live transatlantic television signal.
• Mid-1960s:
  television receiver circuits.^[75]

By 1963, color television was being broadcast commercially (though not all broadcasts or programs were in color), and the first (radio) communication satellite, Telstar, was launched. In the 1970s,

Mobile phones

In 1947 AT&T commercialized the Mobile Telephone Service. From its start in St. Louis in 1946, AT&T then introduced Mobile Telephone Service to one hundred towns and highway corridors by 1948. Mobile Telephone Service was a rarity with only 5,000 customers placing about 30,000 calls each week. Because only three radio channels were available, only three customers in any given city could make mobile telephone calls at one time.^[76] Mobile Telephone Service was expensive, costing US$15 per month, plus $0.30–0.40 per local call, equivalent to (in 2012 US dollars) about $176 per month and $3.50–4.75 per call.^[77] The Advanced Mobile Phone System analog mobile phone system, developed by Bell Labs, was introduced in the Americas in 1978,^[78][79][80] gave much more capacity. It was the primary analog mobile phone system in North America (and other locales) through the 1980s and into the 2000s.

The development of

"We have been asked 'to consider and advise on the policy to be adopted as regards the Imperial Wireless Services so as to protect and facilitate public interest.' It was impressed upon us that the question was urgent. We did not feel called upon to explore the past or to comment on the delays which have occurred in the building of the Empire Wireless Chain. We concentrated our attention on essential matters, examining and considering the facts and circumstances which have a direct bearing on policy and the condition which safeguard public interests."[82]

When radio was introduced in the early 1920s, many predicted it would kill the phonograph record industry. Radio was a free medium for the public to hear music for which they would normally pay. While some companies saw radio as a new avenue for promotion, others feared it would cut into profits from record sales and live performances. Many record companies would not license their records to be played over the radio, and had their major stars sign agreements that they would not perform on radio broadcasts.^[83][84]

Indeed, the music recording industry had a severe drop in profits after the introduction of the radio. For a while, it appeared as though radio was a definite threat to the record industry. Radio ownership grew from two out of five homes in 1931 to four out of five homes in 1938. Meanwhile, record sales fell from $75 million in 1929 to $26 million in 1938 (with a low point of $5 million in 1933), though the economics of the situation were also affected by the Great Depression.^[85]

The copyright owners were concerned that they would see no gain from the popularity of radio and the ‘free’ music it provided. What they needed to make this new medium work for them already existed in previous copyright law. The copyright holder for a song had control over all public performances ‘for profit.’ The problem now was proving that the radio industry, which was just figuring out for itself how to make money from advertising and currently offered free music to anyone with a receiver, was making a profit from the songs.

The test case was against Bamberger's Department Store in Newark, New Jersey in 1922. The store was broadcasting music from its store on the radio station WOR. No advertisements were heard, except at the beginning of the broadcast which announced "L. Bamberger and Co., One of America's Great Stores, Newark, New Jersey." It was determined through this and previous cases (such as the lawsuit against Shanley's Restaurant) that Bamberger was using the songs for commercial gain, thus making it a public performance for profit, which meant the copyright owners were due payment.

With this ruling the American Society of Composers, Authors and Publishers (ASCAP) began collecting licensing fees from radio stations in 1923. The beginning sum was $250 for all music protected under ASCAP, but for larger stations the price soon ballooned to $5,000. Edward Samuels reports in his book The Illustrated Story of Copyright that "radio and TV licensing represents the single greatest source of revenue for ASCAP and its composers […] and [a]n average member of ASCAP gets about $150–$200 per work per year, or about $5,000-$6,000 for all of a member's compositions." Not long after the Bamberger ruling, ASCAP had to once again defend their right to charge fees, in 1924. The Dill Radio Bill would have allowed radio stations to play music without paying and licensing fees to ASCAP or any other music-licensing corporations. The bill did not pass.^[86]

Regulations of radio stations in the U.S

Wireless Ship Act of 1910

Radio technology was first used for ships to communicate at sea. To ensure safety, the Wireless Ship Act of 1910 marks the first time the U.S. government implies regulations on radio systems on ships.^[87] This act requires ships to have a radio system with a professional operator if they want to travel more than 200 miles offshore or have more than 50 people on board. However, this act had many flaws including the competition of radio operators including the two majors company (British and American Marconi). They tended to delay communication for ships that used their competitor's system. This contributed to the tragic incident of the sinking of the Titanic in 1912.

Radio Act of 1912

In 1912, distress calls to aid the sinking Titanic were met with a large amount of interfering radio traffic, severely hampering the rescue effort. Subsequently, the US government passed the Radio Act of 1912 to help mitigate the repeat of such a tragedy. The act helps distinguish between normal radio traffic and (primarily maritime) emergency communication, and specifies the role of government during such an emergency.^[88]

The Radio Act of 1927

The Radio Act of 1927 gave the Federal Radio Commission the power to grant and deny licenses, and to assign frequencies and power levels for each licensee. In 1928 it began requiring licenses of existing stations and setting controls on who could broadcast from where on what frequency and at what power. Some stations could not obtain a license and ceased operations. In section 29, the Radio Act of 1927 mentioned that the content of the broadcast should be freely present, and the government cannot interfere with this.^[89]

The Communications Act of 1934

The introduction of the Communications Act of 1934 led to the establishment of the Federal Communications Commissions (FCC). The FCC's responsibility is to control the industry including "telephone, telegraph, and radio communications."^[90] Under this Act, all carriers have to keep records of authorized interference and unauthorized interference. This Act also supports the President in time of war. If the government needs to use the communication facilities in time of war, they are allowed to.

The Telecommunications Act of 1996

The Telecommunications Act of 1996 was the first significant overhaul in over 60 years amending the work of the Communications Act of 1934. Coming only two dozen years after the breakup of AT&T, the act sets out to move telecommunications into a state of competition with their markets and the networks they are a part of.^[91] Up to this point the effects of the Telecommunications Act of 1996 have been seen, but some of the changes the Act set out to fix are still ongoing problems, such as being unable to create an open competitive market.

Licensed commercial public radio stations

The question of the 'first' publicly targeted licensed radio station in the U.S. has more than one answer and depends on semantics. Settlement of this 'first' question may hang largely upon what constitutes 'regular' programming

• It is commonly attributed to KDKA in Pittsburgh, Pennsylvania, which in October 1920 received its license and went on the air as the first US licensed commercial broadcasting station on November 2, 1920, with the presidential election results as its inaugural show, but was not broadcasting daily until 1921. (Their engineer Frank Conrad had been broadcasting from on the two call sign signals of 8XK and 8YK since 1916.) Technically, KDKA was the first of several already-extant stations to receive a 'limited commercial' license.^[92]
• On February 17, 1919, station 9XM at the University of Wisconsin in Madison broadcast human speech to the public at large. 9XM was first experimentally licensed in 1914, began regular Morse code transmissions in 1916, and its first music broadcast in 1917. Regularly scheduled broadcasts of voice and music began in January 1921. That station is still on the air today as WHA.^[93]
• On August 20, 1920, 8MK, began broadcasting daily and was later claimed by famed inventor Lee de Forest as the first commercial station. 8MK was licensed to a teenager, Michael DeLisle Lyons, and financed by E. W. Scripps. In 1921 8MK changed to WBL and then to WWJ in 1922, in Detroit. It has carried a regular schedule of programming to the present and also broadcast the 1920 presidential election returns just as KDKA did.^[94] Inventor Lee de Forest claims to have been present during 8MK's earliest broadcasts, since the station was using a transmitter sold by his company.^[95]
• The first station to receive a commercial license was
  U.S. Department of Commerce showed that WBZ received its commercial license on 15 September 1921; another Westinghouse station, WJZ, then in Newark, New Jersey, received its commercial license on November 7, the same day as KDKA did.^[96]
  What separates WJZ and WBZ from KDKA is the fact that neither of the former stations remain in their original city of license, whereas KDKA has remained in Pittsburgh for its entire existence.
• 2XG: Launched by Lee de Forest in the Highbridge section of New York City, that station began daily broadcasts in 1916.^[97]
  Like most experimental radio stations, however, it had to go off the air when the U.S. entered World War I in 1917, and did not return to the air.
• 1XE: Launched by Harold J. Power in Medford, Massachusetts, 1XE was an experimental station that started broadcasting in 1917. It had to go off the air during World War I, but started up again after the war, and began regular voice and music broadcasts in 1919. However, the station did not receive its commercial license, becoming WGI, until 1922.^[98]
• WWV, the U.S. Government time service, which was believed to have started 6 months before KDKA in Washington, D.C. but in 1966 was transferred to Ft. Collins, Colorado.^[99]
• WRUC, the Wireless Radio Union College, located on Union College in Schenectady, New York; was launched as W2XQ ^[100]
• KQV, one of Pittsburgh's five original AM stations, signed on as amateur station "8ZAE" on November 19, 1919, but did not receive a commercial license until January 9, 1922.

See also

Histories

• History of electrical engineering
• History of electromagnetic theory
• History of electromagnetic spectrum
• History of amateur radio
• History of broadcasting
• History of music
• History of physics
• History of podcasting
• History of radar
• History of science and technology
• History of telecommunication
• History of television
• History of videotelephony

General

Many contributed to wireless. Individuals that helped to further the science include, among others:

Categories

Footnotes

References

Primary sources

• De Lee Forest. Father of Radio: The Autobiography of Lee de Forest (1950).
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• Lichty Lawrence W., and Topping Malachi C., eds. American Broadcasting: A Source Book on the History of Radio and Television (Hastings House, 1975).

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  LCCN 86-35439
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  LCCN 77-472455
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• McChesney, Robert W. Telecommunications, Mass Media, and Democracy: The Battle for the Control of U.S. Broadcasting, 1928–1935 Oxford University Press, 1994
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• The Prestige, 2006, Touchstone Pictures.
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• Schwoch James. The American Radio Industry and Its Latin American Activities, 1900–1939 (University of Illinois Press, 1990).
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• Weightman, Gavin, "Signor Marconi's magic box : the most remarkable invention of the 19th century & the amateur inventor whose genius sparked a revolution" 1st Da Capo Press ed., Cambridge, Massachusetts : Da Capo Press, 2003.
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Media and documentaries

• ISBN 0060182156

External links

Wikimedia Commons has media related to History of radio.

• "A Comparison of the Tesla and Marconi Low-Frequency Wireless Systems ". Twenty First Century Books, Breckenridge, Co.
• Sparks Telegraph Key Review
• "Presentation of the Edison Medal to Nikola Tesla". Minutes of the Annual Meeting of the American Institute of Electrical Engineers. Held at the Engineering Society Building, New York City, Friday evening, May 18, 1917.
• Timeline of the First Thirty Years of Radio 1895–1925 Archived 2008-03-31 at the Wayback Machine; An important chapter in the Death of Distance. Nova Scotia, Canada, March 14, 2006.
• Cybertelecom :: Radio History (legal and regulatory)
• Western Historic Radio Museum: Radio Communication Equipment from 1909 to 1959.