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Radio

Radio

Background

The radio receives electromagnetic waves from the air that are sent by a radio transmitter. Electromagnetic waves are a combination of electrical and magnetic fields that overlap. The radio converts these electromagnetic waves, called a signal, into sounds that humans can hear.

Radios are a part of everyday life. Not only are they used to play music or as alarms in the morning, they are also used in cordless phones, cell phones, baby monitors, garage door openers, toys, satellites, and radar. Radios also play an important role in communications for police, fire, industry, and the military. Although there are many types of radios—clock, car, amateur (ham), stereo—all contain the same basic components.

Radios come in all shapes and sizes, from a little AM/FM "Walkman" to a highly sophisticated, multi-mode transceiver where both the transmitter and receiver are combined in one unit. The most common modes for a broadcast radio are AM (amplitude modulation) and FM (frequency modulation). Other modes used by ham radio operators, industry, and the military are CW (continuous wave using Morse code), SSB (single sideband), digital modes such as telemetry, radio teletype, and PSK (phase shift keying).

History

Guglielmo Marconi successfully sent the first radio message across the Atlantic Ocean in December 1901 from England to Newfoundland. Marconi's radio did not receive voice or music. Rather, it received buzzing sounds created by a spark gap transmitter sending a signal using Morse code.

The radio got its voice on Christmas Eve 1906. As dozens of ship and amateur radio operators listened for the evening's traffic messages, they were amazed to hear a man's voice calling "CQ, CQ" (which means calling all stations, I have messages) instead of the customary dits and dahs of Morse code. The message was transmitted by Professor Reginald Aubrey Fessenden from a small radio station in Brant Rock, Massachusetts.

In the years from 1904 to 1914, the radio went through many refinements with the invention of the diode and triode vacuum tubes. These devices enabled better transmission and reception of voice and music. Also during this time period, the radio became standard equipment on ships crossing the oceans.

The radio came of age during World War I. Military leaders recognized its value for communicating with the infantry and ships at sea. During the WWI, many advancements were made to the radio making it more powerful and compact. In 1923, Edwin Armstrong invented the superhetrodyne radio. It was a major advancement in how a radio worked. The basic principles used in the superhetrodyne radio are still in use today.

On November 2, 1920 the first commercial radio station went on the air in Pittsburgh, Pennsylvania. It was an instant success, and began the radio revolution called the "Golden Age of Radio." The Golden Age of Radio lasted from the early 1920s through the late 1940s when television brought in a whole new era. During this Golden Age, the radio evolved from a simple device in a bulky box to a complex piece of equipment housed in beautiful wooden cabinets. People would gather around the radio and listen to the latest news and radio plays. The radio occupied a similar position as today's television set.

On June 30, 1948 the transistor was successfully demonstrated at Bell Laboratories. The transistor allowed radios to become compact, with the smallest ones able to fit in a shirt pocket. In 1959, Jack Kilby and Robert Noyce received the first patent for the integrated circuit. The space program of the 1960s would bring more advances to the integrated circuit. Now, a radio could fit in the frame of eyeglasses or inside a pair of small stereo earphones. Today, the frequency dial printed on the cabinet has been replaced with light emitting diodes or liquid crystal displays.

Raw Materials

Today's radio consists of an antenna, printed circuit board, resistors, capacitors, coils and transformers, transistors, integrated circuits, and a speaker. All of these parts are housed in a plastic case.

An internal antenna consists of small-diameter insulated copper wire wound around a ferrite core. An external antenna consists of several aluminum tubes that slide within one another.

The printed circuit board consists of a copper-clad pattern cemented to a phenolic board. The copper pattern is the wiring from component to component. It replaces most of the wiring used in earlier radios.

Resistors limit the flow of electricity. They consist of a carbon film deposited on a cylindrical substrate, encased in a plastic (alkyd polyester) housing, with wire leads made of copper.

Capacitors store an electrical charge and allow alternating current to flow through an electrical circuit but prevent direct current from flowing in the same circuit. Fixed capacitors consist of two extended aluminum foil electrodes insulated by polypropylene film, housed in a plastic or ceramic housing with copper wire leads. Variable capacitors have a set of fixed aluminum plates and a set of rotating aluminum plates with an air insulator.

Coils and transformers perform similar functions. Their purpose is to insulate a circuit while transferring energy from one circuit to another. They consist of two or more sets of copper wire coils either wound on an insulator or mounted side-by-side with air as the insulator.

Transistors consist of germanium or silicon encased in a metal housing with copper wire leads. The transistor controls the flow of electricity in a circuit. Transistors replaced vacuum tubes used in earlier radios.

The integrated circuit houses thousands of resistors, capacitors, and transistors into a small and compact package called a chip. This chip is about the size of the nail on the little finger. The chip is mounted in a plastic case with aluminum tabs that allow it to be mounted to a printed circuit board.

Design

Radios consist of many specialized electronic circuits designed to perform specific tasks—radio frequency amplifier, mixer, variable frequency oscillator, intermediate frequency amplifier, detector, and audio amplifier.

The radio frequency amplifier is designed to amplify the signal from a radio broadcast transmitter. The mixer takes the radio signal and combines it with another signal produced by the radio's variable frequency oscillator to produce an intermediate frequency. The variable frequency oscillator is the tuning knob on the radio. The produced intermediate frequency is amplified by the intermediate frequency amplifier. This intermediate signal is sent to the detector which converts the radio signal to an audio signal. The audio amplifier amplifies the audio signal and sends it to the speaker or earphones.

The simplest AM/FM radio will have all of these circuits mounted on a single circuit board. Most of these circuits can be contained in a single integrated circuit. The volume control (a variable resistor), tuning knob (a variable capacitor), speaker, antenna, and batteries can be mounted either on the printed circuit board or in the radio's case.

The Manufacturing
Process

There is no single process for manufacturing a radio. The manufacturing process depends upon the design and complexity of the radio. The simplest radio has a single circuit board housed in a plastic case. The most complex radio has many circuit boards or modules housed in aluminum case.

Manufacturers purchase the basic components such as resistors, capacitors, transistors, integrated circuits, etc., from vendors and suppliers. The printed circuit boards, usually proprietary, may be manufactured in house. Many times, manufacturers will purchase complete radio modules from an vendor. Most of the manufacturing operations are performed by robots. These include the printed circuit boards and mounting of the components on the printed circuit board. Mounting of the printed circuit board and controls into the case and some soldering operations are usually done by hand.

  1. The blank printed circuit board consists of a glass epoxy resin with a thin copper film cemented to one or both sides. A light sensitive photoresist film is placed over the copper film. A mask containing the electrical circuitry is placed over the photoresist film. The photoresist film is exposed to ultraviolet light. The photoresist image is developed, transferring the image to the copper film. The unexposed areas dissolve during etching and produce a printed circuit on the board.
  2. Holes are drilled in designated locations on the printed circuit board to accept the components. Then, the board is pre-soldered by dipping it in a bath of hot solder.
  3. Smaller electronic components such as resistors, capacitors, transistors, integrated circuits, and coils are installed in their designated holes on the printed circuit board and soldered to the board. These operations can be performed by hand or by robots.
  4. Larger components such as power transformer, speaker, and antenna are mounted either on the PCB or cabinet with screws or metal spring tabs.
  5. The case that houses the radio can be made either of plastic or aluminum. Plastic cases are made from pellets that are melted and injected into a mold. Aluminum cases are stamped into shape from sheet aluminum by a metal press.
  6. External components not mounted on the printed circuit board can be the antenna, speaker, power transformer, volume, and frequency controls are mounted in the case with either screws, rivets, or plastic snaps. The printed circuit board is then mounted in the case with screws or snaps. The external components are connected and soldered to the printed circuit board with insulated wires made of copper and plastic insulation.

Quality Control

Since most of the components or a radio are manufactured by specialized vendors, the radio manufacturer must rely on those venders to produce quality parts. However, the radio manufacturer will take random samples of each component received and inspect/test them to ensure they meet the required specifications.

Random samples of the final radio assembly are also inspected to ensure quality. The overall unit is inspected for flaws—both physical and electrical. The radio is played to ensure it can select radio frequencies it's design to receive, and that the audio output is within specifications.

Byproducts/Waste

Today's environmental awareness dictates that all waste be disposed of properly. Most byproducts from the construction of a radio can be reclaimed. The etching solutions used in the printed circuit board manufacture are sent to chemical reclamation centers. Scraps from the leads of electronic components are sent to metal waste recovery centers where they are melted to create new products.

The Future

Radios are being combined with computers to connect the computer to the Internet via satellites. Eventually radios will convert from analog to digital broadcasting. Analog signals are subject to fade and interference, digital signals are not. They can produce high quality sound like that found on a CD.

Digital radios can be programmed for specific stations, types of music, news, etc. Eventually, radios will have mini-computers built in to process sounds in numerical patterns "digits" rather than an analog waveform. This will allow listeners to program their radios for favorite radio stations, music type, stock quotes, traffic information, and much more.

Where to Learn More

Books

Carter, Alden R. Radio From Marconi To The Space Age. New York: Franklin Watts, 1987.

Floyd, Thomas L. Electric Circuit Fundamentals. Columbus: Merrill Publishing Company, 1987.

The American Radio Relay League. The ARRL Handbook for Radio Amateurs. Newington, CT: ARRL, 1996.

Other

Canadian Broadcasting Company Web Page. "The Future of Digital Radio.: December 2001. <http://radioworks.cbc.ca/radio/digital-radio/drri.html>.

UC Berkley Web Page. December 2001. <http://www.cs.berkeley.edu/~gribble/cs39c/Comm/radio/radio.html>.

ErnstS.Sibberson

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Radio

RADIO

RADIO. The Information Age began with the invention of the telegraph and telephone. These innovations led directly to the next important technological break-through—the arrival of commercial radio. Almost immediately, radio focused on listeners as consumers and the developing consumer culture, which would be replicated later with television, motion pictures, and most recently, the Internet. Radio transformed people's lives, changing the way living space was arranged, shaping family dynamics and leisure time, and reinforcing the ideals of the growing consumer culture.

Throughout its history, radio has not only been a driving force in American popular culture, but has basically provided the soundtrack for people's lives. Despite the all-encompassing influence of television, movies, and the Internet, radio remains at the core of the public's being. While some listeners tune in for music (spanning the spectrum from classic rock to rap) and others for talk (politics, sports, culture, and religion), radio continues to be a central component in shaping lives—musically, spiritually, politically, and culturally.

Early Days

Radio pioneers built on the success of telegraph and telephone inventors to conduct experiments with wire-based and wireless radio. Heinrich Hertz and Guglielmo Marconi carried out groundbreaking work. In 1901, Marconi gained international fame by sending a message across the Atlantic Ocean via wireless telephony. Early triumphs spurred greater advances. By the 1910s, Lee De Forest broadcast music and voice from his lab in New York. Early advocates championed the use of radio as an emergency device, citing how it was used when the Titanic sank in 1912 or during World War I (1914–1918).

In November 1920, Pittsburgh's station KDKA initiated America's first radio broadcast. Operated by the Westinghouse Corporation, KDKA was set up to en-courage radio sales. Other large companies followed suit, including the Radio Corporation of America (RCA) and the phone company AT&T. Within two years, more than 500 stations were clogging the airwaves. The federal government stepped in to regulate radio stations with the Radio Act of 1927, which established the Federal Radio Commission to license stations. The need for regulating the entire telecommunications industry later led President Franklin D. Roosevelt to support the Communications Act of 1934, which established the Federal Communications Commission (FCC).

Radio stations first sold advertising in 1922 at New York station WEAF. In 1926 and 1927, NBC (NBC-Red and NBC-Blue) and CBS were founded as national radio stations, although there were 700 other stations on the air at the time. Along with the Mutual Broadcasting System (MBS), these stations controlled the airwaves for most of radio's heyday. Since RCA owned both NBC stations, it was ordered by the FCC to divest one. In 1943, NBC-Blue became ABC.

Golden Age

The period leading up to the introduction of television is considered radio's Golden Age. Radio transformed people's lives from the late 1920s to late 1940s by providing news and entertainment to anyone who could afford a


receiver. Specific audience-friendly programming was introduced to lure listeners, from half-hour sitcoms to daytime dramas and music programs. Radio had a grip on the nation's psyche, as seen on Halloween 1938 when Orson Welles narrated a dramatization of the book War of the Worlds by H. G. Wells. A panic ensued when listeners believed the news that invaders from Mars were attacking the world, despite many disclaimers that were run throughout the broadcast.

The national networks solidified their hold during the Golden Age. Local stations lost their monopolistic control over programming and as network affiliates, were contractually obliged to play the shows emanating from the larger stations. The networks delivered more sophisticated programs and made national stars of performers such as Will Rogers and Freeman Gosden and Charles Correll, better known as Amos 'n' Andy, the most popular show in America by 1929. The networks played an important cultural role, since they delivered the same programming nationwide. Radio helped promote national values and attitudes, making radio one of the few threads that tied the entire nation together. By the late 1940s, more than 90 percent of the homes in the nation had at least one radio and Americans spent more leisure time listening to the radio than doing anything else other than sleeping.

As radio developed, the kind of programs it offered changed as well. Action series, such as The Shadow and The Green Hornet, helped define how people thought about law enforcement. The medium endorsed a hero culture to listeners, from broadcasting the heroic efforts of baseball's Babe Ruth to the intergalactic exploits of Flash Gordon.

Radio had a tremendous impact on politics and journalism. President Franklin D. Roosevelt used the radio to mobilize support for his New Deal programs in "fireside chats" with the American people. As World War II (1939– 1945) loomed, the president used the radio to stoke the public's patriotic fever. Once the war began, correspondents, such as Edward R. Murrow, Walter Cronkite, and Eric Sevareid, delivered reports from the European front-lines, forever changing reporting and in essence inventing broadcast journalism.

During World War II, most people experienced the war most forcefully through radio. In addition to the breaking news, presidential reports, and reports from the frontlines, celebrities used radio to pitch for war bonds and plead for scrap metal drives and other resources. Paper shortages during wartime limited the influence of


newspapers. Radio stations stepped into this void and provided a mix of news, reports, and patriotic messages that listeners craved.

Advertisers realized the power of radio and poured money into commercials. In 1928, radio garnered less than 1 percent of all advertising. By 1945, however, radio commanded 15 percent. In 1948, sponsors spent more than $400 million on radio advertising. The financial growth of radio was mimicked by the expansion of stations themselves. In 1930 there were 600 amplitude modulation (AM) stations. A decade later, the figure jumped to 765. But by 1948, it more than doubled to 1,612.

Radio in the Television Age

Frequency modulation (FM) radio developed in the late 1930s, when E. Howard Armstrong searched for a way to broadcast without the static common on AM dials. The AM dial also became overcrowded during radio's Golden Age. Inventors looked for an alternative to mainstream radio, which coincided with the anticommercialism of the 1960s.

The decade's youth culture helped spur the growth of FM stations. Listeners were antitelevision and anticonformity and could find a similar rebelliousness in the songs and programs on FM radio. Progressive rock stations took root in San Francisco, Los Angeles, New York, and Boston, eliminating advertising jingles and the antics of AM disc jockeys.

Gradually, the FM dial went through the same commercial transformation that occurred with AM. Initially, the networks started exerting their influence on FM, attempting to maintain a delicate balance between commercialism and FM's underground roots. By the end of the 1970s, however, the demand for profits and fall of the counterculture movement made FM radio look just like its AM predecessor, with the large networks squeezing out the remnants of the underground heritage. Revenues at FM stations, under $20 million in 1964, hit $284 million a decade later. There were more than 2,300 stations on air in 1972, but 3,700 by 1976. In 1977, FM revenues topped $543 million, but programming was done by committee and depended on computerization. An assembly line mentality took hold and the same rotations of hit songs were played over and over.

Modern Radio

Modern radio is far removed from its origins. At one time, pioneering entrepreneurs influenced radio and introduced diversity into programming. At the end of the twentieth century, corporate conglomerates governed the industry and a general uniformity had befallen radio. Despite the homogeneity of modern radio, however, its influence is still strong. By 2000, there were more than 12,000 AM and FM stations broadcast, with much of the programming distributed by satellite networks.

The cookie-cutter mentality at most radio stations from the 1980s onward led to the rise of talk radio, from National Public Radio (NPR) to political and sportsoriented shows. Talk radio opened the airwaves to a variety of voices and made celebrities of hosts like Howard Stern, Rush Limbaugh, and Diane Rehm. Stern, in particular, gained notoriety as a "shock jock." His show is syndicated via satellite nationwide and features racy bits and an in-your-face attitude that launched a slew of imitators. The number of stations with all-talk or news and talk format topped 850 in 1994, and talk radio placed second among popular formats, with country music at the top.

The domination of the radio industry by large corporations was helped by the passage of the Telecommunications Act of 1996, which eliminated restrictions on radio ownership. Before, companies could only own two stations in any single market and 28 nationwide. All this changed after the Telecom Act passed. For example, as of 2002, Clear Channel Radio was the largest operator of radio stations in the United States with more than 1,350 stations and reaching 110 million listeners every week. Clear Channel also syndicated more than 100 programs to 7,800 stations, including Rush Limbaugh, sports talk leader Jim Rome, and Casey Kasem. Nearly half (625) of Clear Channel's radio stations were purchased in the 1999 Jacor acquisition.

The Telecom Act pushed radio acquisitions into overdrive. The feeding frenzy, driven by an influx of Wall Street money, enabled a handful of conglomerates to take control of the industry. Although radio is now more profitable, critics rebuke the conglomerates for forcing staid, automated music and formats on listeners, as well as for the elimination of countless radio jobs. Regardless of its shortcomings, however, radio continues to attract listeners and frames the way people think about music, sports, politics, and culture. In 2001, there were nearly 13,000 stations in the United States, which reached 77 percent of the people over 12 years old every day and 95 percent of consumers weekly.

BIBLIOGRAPHY

Barnouw, Erik. A History of Broadcasting in the United States. 3 Vols. New York: Oxford University Press, 1966–1970.

Douglas, Susan J. Listening In: Radio and the American Imagination, from Amos 'n' Andy and Edward R. Murrow to Wolfman Jack and Howard Stern. New York: Times Books, 1999.

Keith, Michael C. Talking Radio: An Oral History of American Radio in the Television Age. Armonk, N.Y.: M.E. Sharpe, 2000.

MacDonald, J. Fred. Don't Touch That Dial! Radio Programming in American Life, 1920–1960. Chicago: Nelson-Hall, 1979.

BobBatchelor

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radio

radio, transmission or reception of electromagnetic radiation in the radio frequency range. The term is commonly applied also to the equipment used, especially to the radio receiver.

Uses of Radio Waves

The prime purpose of radio is to convey information from one place to another through the intervening media (i.e., air, space, nonconducting materials) without wires. Besides being used for transmitting sound and television signals, radio is used for the transmission of data in coded form. In the form of radar it is used also for sending out signals and picking up their reflections from objects in their path. Long-range radio signals enable astronauts to communicate with the earth from the moon and carry information from space probes as they travel to distant planets (see space exploration). For navigation of ships and aircraft the radio range, radio compass (or direction finder), and radio time signals are widely used. Radio signals sent from global positioning satellites can also be used by special receivers for a precise indication of position (see navigation satellite). Digital radio, both satellite and terrestrial, provides improved audio clarity and volume. Various remote-control devices, including rocket and artificial satellite operations systems and automatic valves in pipelines, are activated by radio signals. The development of the transistor and other microelectronic devices (see microelectronics) led to the development of portable transmitters and receivers. Cellular and cordless telephones are actually radio transceivers. Many telephone calls routinely are relayed by radio rather than by wires; some are sent via radio to relay satellites. Some celestial bodies and interstellar gases emit relatively strong radio waves that are observed with radio telescopes composed of very sensitive receivers and large directional antennas (see radio astronomy).

Transmission and Reception of Radio Waves

For the propagation and interception of radio waves, a transmitter and receiver are employed. A radio wave acts as a carrier of information-bearing signals; the information may be encoded directly on the wave by periodically interrupting its transmission (as in dot-and-dash telegraphy) or impressed on it by a process called modulation. The actual information in a modulated signal is contained in its sidebands, or frequencies added to the carrier wave, rather than in the carrier wave itself. The two most common types of modulation used in radio are amplitude modulation (AM) and frequency modulation (FM). Frequency modulation minimizes noise and provides greater fidelity than amplitude modulation, which is the older method of broadcasting. Both AM and FM are analog transmission systems, that is, they process sounds into continuously varying patterns of electrical signals which resemble sound waves. Digital radio uses a transmission system in which the signals propagate as discrete voltage pulses, that is, as patterns of numbers; before transmission, an analog audio signal is converted into a digital signal, which may be transmitted in the AM or FM frequency range. A digital radio broadcast offers compact-disc-quality reception and reproduction on the FM band and FM-quality reception and reproduction on the AM band.

In its most common form, radio is used for the transmission of sounds (voice and music) and pictures (television). The sounds and images are converted into electrical signals by a microphone (sounds) or video camera (images), amplified, and used to modulate a carrier wave that has been generated by an oscillator circuit in a transmitter. The modulated carrier is also amplified, then applied to an antenna that converts the electrical signals to electromagnetic waves for radiation into space. Such waves radiate at the speed of light and are transmitted not only by line of sight but also by deflection from the ionosphere.

Receiving antennas intercept part of this radiation, change it back to the form of electrical signals, and feed it to a receiver. The most efficient and most common circuit for radio-frequency selection and amplification used in radio receivers is the superheterodyne. In that system, incoming signals are mixed with a signal from a local oscillator to produce intermediate frequencies (IF) that are equal to the arithmetical sum and difference of the incoming and local frequencies. One of those frequencies is applied to an amplifier. Because the IF amplifier operates at a single frequency, namely the intermediate frequency, it can be built for optimum selectivity and gain. The tuning control on a radio receiver adjusts the local oscillator frequency. If the incoming signals are above the threshold of sensitivity of the receiver and if the receiver is tuned to the frequency of the signal, it will amplify the signal and feed it to circuits that demodulate it, i.e., separate the signal wave itself from the carrier wave.

There are certain differences between AM and FM receivers. In an AM transmission the carrier wave is constant in frequency and varies in amplitude (strength) according to the sounds present at the microphone; in FM the carrier is constant in amplitude and varies in frequency. Because the noise that affects radio signals is partly, but not completely, manifested in amplitude variations, wideband FM receivers are inherently less sensitive to noise. In an FM receiver, the limiter and discriminator stages are circuits that respond solely to changes in frequency. The other stages of the FM receiver are similar to those of the AM receiver but require more care in design and assembly to make full use of FM's advantages. FM is also used in television sound systems. In both radio and television receivers, once the basic signals have been separated from the carrier wave they are fed to a loudspeaker or a display device (usually a cathode-ray tube), where they are converted into sound and visual images, respectively.

Development of Radio Technology

Radio is based on the studies of James Clerk Maxwell, who developed the mathematical theory of electromagnetic waves, and Heinrich Hertz, who devised an apparatus for generating and detecting them. Guglielmo Marconi, recognizing the possibility of using these waves for a wireless communication system, gave a demonstration (1895) of the wireless telegraph, using Hertz's spark coil as a transmitter and Edouard Branly's coherer (a radio detector in which the conductance between two conductors is improved by the passage of a high-frequency current) as the first radio receiver. The effective operating distance of this system increased as the equipment was improved, and in 1901, Marconi succeeded in sending the letter S across the Atlantic Ocean using Morse code. In 1904, Sir John A. Fleming developed the first vacuum electron tube, which was able to detect radio waves electronically. Two years later, Lee de Forest invented the audion, a type of triode, or three-element tube, which not only detected radio waves but also amplified them.

Radio telephony—the transmission of music and speech—also began in 1906 with the work of Reginald Fessiden and Ernst F. W. Alexanderson, but it was not until Edwin H. Armstrong patented (1913) the circuit for the regenerative receiver that long-range radio reception became practicable. The major developments in radio initially were for ship-to-shore communications. Following the establishment (1920) of station KDKA at Pittsburgh, Pa., the first commercial broadcasting station in the United States, technical improvements in the industry increased, as did radio's popularity. In 1926 the first broadcasting network was formed, ushering in the golden age of radio. Generally credited with creating the first modern broadband FM system, Armstrong built and operated the first FM radio station, KE2XCC, in 1938 at Alpine, N.J. The least expensive form of entertainment during the Great Depression, the radio receiver became a standard household fixture, particularly in the United States. Subsequent research gave rise to countless technical improvements and to such applications as radio facsimile, radar, and television. The latter changed radio programming drastically, and the 1940s and 50s witnessed the migration of the most popular comedy and drama shows from radio to television. Radio programming became mostly music and news and, to a lesser extent, talk shows. The turn of the century saw a potential rebirth for radio as mobile digital radio entered the market with a satellite-based subscription service in Europe (1998) and in the United States (2000). Two years later, a land-based digital radio subscription service was inaugurated in the United States.

Radios that combine transmitters and receivers are now widely used for communications. Police and military forces and various businesses commonly use such radios to maintain contact with dispersed individuals or groups. Citizens band (CB) radios, two-way radios operating at frequencies near 27 megahertz, most typically used in vehicles for communication while traveling, became popular in the 1970s. Cellular telephones, despite the name, are another popular form of radio used for communication.

Bibliography

See A. and W. Marcus, Elements of Radio (6th ed. 1973); D. L. Schilling, Principles of Communications Systems (2d ed. 1986).

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Radio

Radio


In the 1930s and 1940s, when radio still was regarded as a new medium, special children's programs were broadcast in order to attract young listeners. As such programs became popular, production increased. Children and teenagers took pleasure in listening to programs specifically aimed at children as well as other programs. By this time, American children aged nine to twelve listened to radio approximately two to three hours a day, especially during the evening. Girls preferred romantic and historical dramatizations and boys listened more to popular and novelty programs, but one study came to the conclusion that the differences mattered less than the similarities. With some variations, comedy and mystery radio plays were preferred above others by both boys and girls of all ages. Thus children enjoyed a variety of programs, including those produced for adults.

As with other electronic media, radio was met with worries from the adult world. In Sweden, as in other countries, it was a common anxiety that too much listening could make children passive and less eager to play. In the 1940s, Swedish teachers expressed worries about being regarded as mere "loudspeakers" by children accustomed to passively listening to radio. However, compared with reactions to other electronic media, radio seems to have incited relatively few "moral panic" attacks. Partly this can be explained by radio's supposed usefulness in education (discussed below).

In the 1950s, when television was introduced, researchers in Britain came to the conclusion that television reduced radio listening more than it reduced any other activity. In spite of this, one in three children said that if they had to do without radio they would miss it quite a lot. The study also noticed that children who had been watching television for several years listened a little more often to the radio. This was described as a revival in line with reports of adults' media behavior. While radio plays could not compete with television plays, other types of programs held listeners' interest, including panel games, discussions, music, and sports commentaries.

Other studies have arrived at the similar conclusion that, with increasing age, children spent more time with radio than with television. Teenagers in particular have been found to be regular radio listeners. Researchers have attributed this to the socialization effects of radio, although explanations of what those effects are have varied over time. In the 1970s socialization to political virtues was considered to be an important factor, while in the 1980s, radio was seen as a source for identity formation in a peer group. This change can be related to the shift of content in programs addressed to teenagers. In the 1980s and 1990s teenagers listened more to music than to anything else on radio.

Radio in Education

From the start, in both Europe and America radio was greeted with hopes for its pedagogical value. Radio had the power to bring the world to the classroom, and programs could be presented as textbooks of the air.

In America, commercial and educational stations received licenses starting in the 1920s to produce classroom broadcasting, and eventually national networks also provided educational programs. Even though most programs were in line with traditional school subjects, some attempted to connect this content with progressive ideas about education and democracy. Radio allowed children and teachers to engage in the production of programs, preparing talks on, for example, automobiles, farming, and science. Together with the fact that parents supplied schools with radio receivers, this reflected a certain degree of local engagement in the implementation of radio in schools. However, this is not a perspective that has been emphasized in research. On the contrary, the organization of radio in education in America has been described as top down implementation. One example of this was the fact that superintendents, not teachers, were supposed to answer questionnaires, indicating that teachers were not included in the implementation process.

In contrast to America, broadcast systems in Europe were organized as nationwide networks that could be used for the inculcation of national values and virtues. Issues regarding educational as well as social and cultural policy were included in the broadcast organizationsin other words, they became part of welfare policy. In this context, children became a special interest.

In Scandinavian countries and Britain, special departments for educational programs were organized in the late 1920s or early 1930s. In general these programs were in line with the overall curriculum. However, a study on the use of radio in classrooms in Sweden reveals that there were contrasts between the content of ordinary schoolbooks and the content of radio programs. Radio programs emphasized contemporary progressive ideas on education and progressive political notions that were not represented in schoolbooks at that time. Citizenship, a new subject, was also given a particularly radical formulation in the school programs. This meant that children who listened to educational programs on the radio, discussed the programs, and did assignments on them, encountered views of society that differed from prevailing traditional middle-class representations. Reoccurring subjects included the everyday lives of the working or lower-middle classes as well as the need for health reform and an expanded welfare system.

In Sweden, educational broadcasts addressed children not only as future citizens but also as active contemporary citizens. Children were included in the actual broadcasts, where they were displayed, with references to famous scientific explorers like Sven Hedin, as competent explorers of their own society. Further, these children were enlisted to represent various parts of society in accordance with notions of society proposed by progressive policymakers. Each pupil was supposed to have his or her own program sheet where each program was presented in texts and pictures. The notion was that the material should help children to create "listening pictures" (hörbilder ) when listening to programs. This practice was implemented out of a strong belief that a will to change the way people thought had to start with strategies that changed the way they talked.

In contrast to America, and in spite of the centralized organization, in Sweden teachers were included in the implementation of radio in education. They participated continually in surveys where they reported their own and the pupils' responses to programs. Active teachers were invited to annual conferences about the use of radio in classrooms. It was argued by teachers and by the organizers of school broadcasts that elementary schoolteachers were more competent than academics and experts in communicating with pupils and therefore were invited to produce programs.

In Britain, educational radio programs were regarded as an important way to influence individual children and adolescents when they had problems or needed guidance in societal matters. Radio was also used to inculcate new notions of citizenship.

Further Research

Studies of children's radio programs, particularly educational programs, offers an area of research that brings new perspectives to social, cultural, and political history. Such research also expands investigations of children's increased visibility and status as a special group in society, for instance as reflected in the UN Convention on the Rights of the Child (1989). Children's programs provide material for inquiries into children's place in society as well as representations of childhood from a historical perspective, particularly during the period from 1920 to 1960, when radio was regarded as the major electronic medium in society. It is also a field well attuned to further developments of theoretical and methodological issues. In addition to actual programs, manuscripts, program sheets, and other documents concerning children's broadcasts, a number of studies measure children's reading and comprehension skills in relation to radio. Such materials could be used to investigate the systems of knowledge and meaning that have affected the child in different decades of the twentieth century.

See also: Media, Children and the.

bibliography

Christenson, Peter G., and Peter DeBenedittis. 1986. "'Eavesdropping' on the FM Band: Children's Use of Radio." Journal of Communication 36, no. 2: 27-38.

Cuban, Larry. 1986. Teachers and Machines. The Classroom Use of Technology since 1920. New York and London: Teachers College Press.

Lindgren, Anne-Li. 1999. "'Att ha barn med är en god sak': Barn, medier och medborgarskap under 1930-talet" ("Including children is a good thing": Children, media and citizenship in the 1930s). Linköping Studies in Arts and Science 205.

Paik, Haejung. 2000. "The History of Children's Use of Electronic Media. In Handbook of Children and the Media, ed. Dorothy G. Singer and Jerome L. Singer. Thousand Oaks, CA, London, and New Delhi: Sage.

Palmer, Richard. 1947. School Broadcasting in Britain. London: BBC.

Anne-Li Lindgren

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Radio

Radio

Radio is the technology that allows information to be transmitted and received over radio waves. Radio makes it possible to establish wireless two-way communication between individual pairs of transmitters/receivers and it is used for one-way broadcasts to many receivers. Radio signals can carry speech, music, or digitally encoded entertainment. Radio waves occur naturally in space or can be created by people. They are a long-wave form of electromagnetic radiation, or radiation that transmits energy through the interaction of electricity and magnetism.

The history of radio

In the nineteenth century, Scottish physicist James Clerk Maxwell (18311879) developed a mathematical theory proving that magnetism and electricity were related. His theory linking the two forces became known as the electromagnetic theory. He predicted that light is only one type of electromagnetic radiation and that wavelengths should exist below infrared (those situated outside the visible spectrum at the red or long-wavelength end) and above ultraviolet (situated outside the visible spectrum at the violet or short-wavelength end). In the 1880s, German physicist Heinrich Hertz (18571894) discovered extremely long-wavelength radio waves, proving Maxwell's theory.

Italian physicist and engineer Guglielmo Marconi (18741937), fascinated with Hertz's discovery of radio waves, built his first crude radio transmitter and receiver in 1895. In 1901, using his "wireless" (as radio was called then), he sent the first message via signals similar to Morse code (which uses dots and dashes for letters and numbers) across the Atlantic Ocean. In the succeeding years, other scientists improved on Marconi's invention, and it eventually became possible to send voice signals by radio waves.

Radio broadcasting as we know it today began in 1920. Station KDKA in Pittsburgh, Pennsylvania, made the announcement to the few people who owned radio receivers that Warren G. Harding had been elected president of the United States. Within a few years, many homes had radio receivers and several radio stations scheduled regular programming.

Radio waves and frequencies

Although turning on a radio produces sound, radio waves themselves cannot be "heard" and have nothing to do with sound waves. While sound waves are a vibration of the air, radio waves are electromagnetic and a part of the light spectrum. Radio waves travel at a speed of 186,282 miles (299,727 kilometers) per secondthe speed of light. Radio waves travel through the air, surrounding us with vibrations that can only be detected through a radio receiver.

Radio programs begin as sound waves, which microphones change into electrical signals. From the antenna atop the radio station, the electrical signals are broadcast as electromagnetic waves. The receiver picks up the waves in the air, electrically amplifies (enlarges) them, and converts them back into sound through the speaker of the radio in your home.

Although radio waves from many stations surround us all the time, the radio does not receive them all at the same time because the stations broadcast at different frequencies. A frequency is the number of times per second that radio waves vibrate. The numbers on a radio dial represent the frequencies used by radio stations in your area. For example, if the dial is set at 96, the radio signal you hear is broadcasted at 960 kilocycles, or 960,000 cycles per second.

Words to Know

Carrier wave: Radio signal with superimposed information.

Electromagnetic radiation: Radiation that transmits energy through the interaction of electricity and magnetism.

Infrared radiation: Electromagnetic radiation of a wavelength shorter than radio waves but longer than visible light that takes the form of heat.

Modulation: Process by which a characteristic of radio waves, such as amplitude or frequency, is changed to make the waves correspond to a signal or information that is being transmitted.

Ultraviolet radiation: Electromagnetic radiation of a wavelength just shorter than the violet end of the visible light spectrum.

Wavelength: The distance between two peaks in any wave.

Modulation

A radio signal alone, without information (speech, music) added to it, is called a carrier wave. Adding information to a carrier signal is a process called modulation. The simplest modulation method is to vary the strength of the signal. The result is called amplitude modulation, or AM. The method that varies the signal's frequency is known as frequency modulation, or FM. AM radio waves are about 1,000 feet (1,600 kilometers) in wavelength, while FM radio waves are only a few feet in wavelength. Broadcasts on AM radio stations can often be heard for hundreds of miles, especially at night when electromagnetic interference is minimal. Broadcasts on FM stations do not travel such a distance, but they have better sound quality and are not affected by lightning-caused static that often plagues AM broadcasts.

[See also Electromagnetic spectrum ]

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radio

radio was the dominant sound medium of the first half of the 20th cent., and—though now less popular than television—still has a residual power in areas such as news and music. The solution to the technical problem of how to send telegraph and telephone messages without connecting cables was found in the late 19th cent. when wire-less means of communication became viable with the discovery by Hertz of electromagnetic waves. In Britain, Italian inventor Marconi developed the first wireless telegraph in 1896, sending airwave messages in Morse code over the Atlantic in 1901. The development of the thermionic valve in America by Lee de Forest and in Britain by John A. Fleming allowed speech to be turned into radio waves, and the First World War brought rapid developments in this means of transmitting messages on the airwaves.

After the war, electrical companies such as Marconi's experimented with transmitting entertainment items to the many amateur radio receivers throughout Britain. After initial attempts to ban such activities, the government decided to license the experiments, leading to the creation in 1922 of the British Broadcasting Company as a monopoly private consortium of radio companies, responsible to the postmaster-general and supported by a licence fee.

With its elevation to a corporation in 1927, the BBC set the tone for radio in Britain over the next 40 years—a paternalistic diet of information and education, with some concessions to entertainment in the form of light musical and variety items. Challenges from the more populist fare of other radio stations—Radio Luxembourg from 1933, American Forces Radio in the Second World War, and offshore pirate radio stations in the 1960s—brought gradual revision to programming policy. The biggest changes to British radio however came in the early 1970s with government legislation to permit commercial radio, under the name of Independent Local Radio (ILR). Capital and LBC in 1973 were the first of a network of stations that grew up throughout the country over the next few years, under the guidance of the Independent Broadcasting Authority (now the Radio Authority). ILR's populist fare often proved more successful than the BBC national and local radio in certain areas, and under Conservative free enterprise policy in the 1980s and 1990s, the expansion of commercial radio was cemented with licences to new national, regional, local, community, and ethnic stations. The pattern of radio consumption has been irrevocably changed, and the BBC entered the 21st cent. with fundamental questions about its position in British culture and society still unanswered.

Douglas J. Allen

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Radio

RADIO

Radio is looked at as an important tool in educating the general public about health issues. In particular, it is believed that properly developed community radio can encourage community-driven problem solving. At the government level, radio has been used to advise the public on issues such as new health standards and seasonal food warnings.

Examples of radio's role in education and public health awareness are numerous. Sound Partnersa program run by the Benton Foundationprovides grants to public radio stations interested in developing community-oriented educational content for the good of public health. Many talk-radio stations and public broadcasters feature special call-in medical programming and general health information. Public addresses via radio, such as President Clinton's radio talk on May 6, 2000, on food safety, and the radio dissemination of automotive product recalls by the United States National Highway Traffic Safety Administration, also exhibit the effectiveness of radio as a means of informing the public.

While the above services are good for the general public, physicians need to be educated in a different manner. Internet radio involves broadcasting audio content on the Internet so it can be heard anywhere in the world through a computer or WebTV unit. Examples of Internet radio delivery systems include RealNetwork's RealPlayer and Microsoft's Windows Media Player.

Internet radio is important for the public health and medical community because it creates an opportunity for high-quality interactive distance learning and education without geographic limitations. For example, in a normal educational setting doctors would need to go to a special class or conference to educate themselves. Internet radio can provide doctors with an alternative to the traditional continuing education setting.

Neil Schneider

(see also: Mass Media; Mass Media and Tobacco Control; Media Advocacy )

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radio

radio Broadcasting or reception of electromagnetic radiation in the form of radio waves. A transmitter generates a radio signal of fixed frequency (the carrier wave). A microphone converts the sound to be broadcast into a varying electrical signal that combines with the carrier by means of modulation (varying the frequency or amplitude of the carrier). Frequency modulation (FM) minimizes interference and provides greater fidelity than amplitude modulation (AM). The modulated carrier wave passes to an aerial, which transmits it into the atmosphere. At the receiver, another aerial intercepts the signal, and it undergoes ‘detection’, the reverse of modulation, to retrieve the signal. Radio waves travel at the speed of light and are transmitted not only by line-of-sight (ground waves), but also by reflection from the ionosphere (sky waves). Sky waves enable long-range transmission. The ultra high frequency (UHF) and very high frequency (VHF) radio waves used to send signals for television penetrate the ionosphere with little reflection, and long-range broadcasting is made possible by means of artificial satellites. The development of radio was a truly international effort. It stems from the work of Scottish physicist James Clerk Maxwell. German physicist Heinrich Hertz devised an apparatus for the transmission and detection of radio waves. In 1895, Italian physicist Guglielmo Marconi gave a demonstration of the first wireless telegraph, and in 1901 he sent the first transatlantic message using Morse code. In 1904, English engineer Sir John Fleming invented the thermionic valve. In 1906, US physicist Lee De Forest developed the audion triode valve, which was able to detect and amplify radio waves. It remained at the heart of radio and television manufacture until the invention (1948) of the transistor.

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radio

ra·di·o / ˈrādēˌō/ • n. (pl. -os) the transmission and reception of electromagnetic waves of radio frequency, esp. those carrying sound messages: cellular phones are linked by radio rather than wires. ∎  the activity or industry of broadcasting sound programs to the public: she has written much material for radio| [as adj.] a radio station. ∎  radio programs: we used to listen to a lot of radio. ∎  an apparatus for receiving such programs: she turned on the radio. ∎  an apparatus capable of both receiving and transmitting radio messages between individuals, ships, planes, etc.: a ship-to-shore radio. ∎  [in names] a broadcasting station or channel: Monitor Radio. • v. (-oes, -oed) [intr.] communicate or send a message by radio: the pilot radioed for help. ∎  [tr.] communicate with (a person or place) by radio: we'll radio Athens right away.

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Radio

343. Radio

See also 265. MEDIA .

phototelegraphy
the transmission of pictures, print, etc., by means of radio or telegraphy. phototelegraphic, adj.
radiophony
radiotelephony. radiophonic, adj.
radiotechnology
the science and technology of radio engineering. radiotechnologic, radiotechnological, adj. See also 342. RADIATION .
radiotelegraphy
1. the transmitting and receiving of messages by radiotelegraph.
2. the science and technology of the radiotelegraph. radiotelegraphic, adj.
radiotelephony
verbal communication at a distance by radio, using telephones. Also called radiophony . radiotelephonic, adj.
telemechanics
the science of operating or controlling mechanisms by remote control, especially by radio.

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Radio

RADIO


The radio, or "wireless," was born in 1895, when Italian physicist and inventor Guglielmo Marconi (18741937) experimented with wireless telegraphy. The following year Marconi transmitted telegraph signals through the air from Italy to England. By 1897 Marconi founded his own company in London, Marconi's Wireless Telegraph Company, Ltd., which began setting up communication lines across the English Channel to France and completed the project in 1898. In 1900 Marconi established the American Marconi Company. He continued making improvements, including sending out signals on different wavelengths so that multiple messages could be transmitted at one time without interfering with each other. The first trans-Atlantic message, from Cornwall, England, to Newfoundland, Canada, was sent and received in 1901.

At first radio technology was regarded as a novelty and few understood how it could work. But in January 1901 a Marconi wireless station at South Wellfleet, Massachusetts (on Cape Cod), received Morse code messages from Europe as well as faint music and voices. That event changed the perception of radio. Before long, Americans had become accustomed to receiving "radiograms"messages transmitted via the wireless. In 1906 the first radio broadcast of voice and music was made. Ships within a radius of several hundred miles picked up the event, which originated at Brant Rock, Massachusetts, on Christmas Eve. That accomplishment resulted from the invention of another radio pioneer, U.S. engineer Reginald Fessenden (18661932), who patented a high-frequency alternator (1901) capable of generating continuous waves rather than intermittent impulses; his invention became the first successful radio transmitter.

In 1910 U.S. inventor Lee De Forest (18731961), "the father of radio," broadcast the tenor voice of opera singer Enrico Caruso over the airwaves. In 1916 De Forest transmitted the first radio news broadcast. Within three years of the first commercial radio broadcast, there were more than five hundred radio stations in the United States. National networks were organized, including the National Broadcast Company (NBC), the Columbia Broadcasting System (CBS), and the Mutual Broadcasting System (MBS). Congress tried to keep pace with the growth of the communications industry by passing the Radio Acts of 1912 and 1927 and setting up the Federal Communications Commission (FCC) to regulate the airwaves.

During the trying times of the Great Depression (19291939), President Franklin Roosevelt (19331945) spoke directly to the U.S. public using the new medium which broadcast his "fireside chats" from the White House. By the end of the decade radio was woven into the fabric of everyday American life. People across the country, in cities, suburbs, and on farms, tuned in for news and entertainment; they listened to broadcasts of baseball games and other sporting events as well as comedy and variety shows, dramas, and live music programs. Between the 1920s and the 1950s gathering around the radio in the evenings was as common to Americans as watching television is today. Networks offered advertisers national audiences and corporate America eagerly seized the opportunity to speak directly to people in their own homes. The advent of television in the 1950s and its growing popularity over the next two decades changed the role of radio in American life. Having lost their audience to TV, radio programmers seized rock music as a way to reach a wide, albeit a very young, audience. Many argue that the rise of the musical genre kept radio alive. In the decades since, radio programming became increasingly music-oriented; talk and news programming were also popular.

See also: Radio Act, RCA-Victor

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radio

radio XX. abbrev. of radiotelegraphy, -telephony; see next.

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radio

radio •Cleo • Carpaccio • Boccaccio •capriccio • braggadocio • Palladio •cardio • radio • video • audio • rodeo •studio •Caravaggio, DiMaggio •adagio •arpeggio, Correggio •Sergio • radicchio • Tokyo • intaglio •seraglio •billy-o, punctilio •folio, imbroglio, olio, polio, portfolio •cameo • Romeo •Borneo, Tornio •Antonio • Scipio • Scorpio •barrio, Mario •impresario, Lothario, Polisario, Rosario, scenario •stereo • embryo •Blériot, Ontario •vireo • Florio •oratorio, Oreo •curio • Ajaccio • Lazio • nuncio •pistachio •fellatio, Horatio, ratio •ab initio, ex officio •patio • Subbuteo • physio

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Radio

Radio


African-American radio can be divided into three general periods of historical development: blackface radio (19201941), black-appeal radio (19421969), and black-controlled radio (1970 to the present). Blackface radio was characterized by the appropriation of African-American music and humor by white entertainers, who performed their secondhand imitations for a predominantly white listening audience. During this period, black people were essentially outside of the commercial broadcasting loop; they were marginal as both radio entertainers and consumers. In the era of black-appeal radio, African Americans entered into the industry as entertainers and consumers, but the ownership and management of the stations targeting the black radio market remained mostly in the hands of white businessmen. This situation constrained the development of independent black radio operations, while the radio industry in general prospered from it. During the most recent period, African Americans have striven to own and operate their own radio stations, both commercial and public. In addition, they have established black-controlled radio networks and trade organizations. However, the percentage of African-American-owned stations still lags far behind the percentage of black listeners.

The appropriation of black song, dance, and humor by white entertainers who blackened their faces with charcoal goes back to the early days of slavery. The resulting radical stereotypes were embedded in the blackface minstrel tradition, which dominated American popular entertainment in the antebellum period, and remained resilient enough in the postbellum years to reappear in film and radio in the early decades of the twentieth century. Popular black music styles like blues and jazz were first performed on the radio by such white performers as Sophie Tucker, the first singer to popularize W. C. Handy's "Saint Louis Blues," and Paul Whiteman, the so-called king of jazz in the 1920s. A parallel trend developed with respect to black humor with the emergence of Amos 'n' Andy (starring Freeman Gosden and Charles Correll) as radio's most popular comedy series.

Indeed, Amos 'n' Andy was radio's first mass phenomenon: a supershow that attracted 53 percent of the national audience, or 40 million listeners, during its peak years on the NBC network in the early 1930s. In addition, the series provoked the black community's first national radio controversy. Robert Abbot, editor of the Chicago Defender, defended Gosden and Correll's caricatures of black urban life as inoffensive and even humane. Robert Vann, editor of the Pittsburgh Courier, countered by criticizing the series as racist in its portrayal of African Americans. He also launched a petition campaign to have the program taken off the air that amassed 740,000 signaturesbut to no avail, for the Federal Radio Commission ignored it. Meanwhile, Amos 'n' Andy dominated black comedy on radio throughout its heyday as the "national pastime" in the 1930s. In addition to Gosden and Correll, the other major blackface radio entertainers of the era included George Mack and Charles Moran, known as the Two Black Crows on the CBS network, as well as Marlin Hunt, who created and portrayed the radio maid Beulah on the series of the same name.

During the period when blackface comedy performed by whites dominated the portrayal of African Americans over the airways, its audience was mostly white; fewer than one in ten black households owned a radio receiver. There were black entertainers and actors who managed to get hired by the radio industry in the preWorld War II era, and for the most part they were restricted to playing stereotyped roles. The renowned black comedian Bert Williams was the first important black performer to be linked to commercial broadcasting, in the 1920s; he was featured on a New York station doing the same routines he popularized while performing in blackface on the Broadway stage. During the Great Depression, as if to add insult to injury, a number of black actors and actresses who auditioned for radio parts were told that they needed to be coached in the art of black dialect by white coaches if they wanted the jobs. This perverse chain of events happened to at least three African-American performers: Lillian Randolph (Lulu and Leander Show ), Johnny Lee (Slick and Slim Show ), and Wonderful Smith (Red Skelton Show ). The most famous black comic to appear regularly on network radio in the 1930s was Eddie Anderson, who played the role of the butler and chauffeur Rochester on the Jack Benny Show. Anderson was often criticized in the black press for playing a stereotypical "faithful servant" role, even as he was being praised for his economic success and celebrity.

After blackface comedy, the African-American dance music called jazz was the next most popular expression of black culture broadcast over the airways in the 1920s and 1930s. As was the case with humor, the major radio jazz bands were made up of white musicians, and were directed by white bandleaders such as Paul Whiteman, B. A. Rolfe, and Ben Bernie. The first black musicians to be broadcast with some regularity on network radio were New York bandleaders Duke Ellington and Noble Sissle. A number of influential white radio producers such as Frank and Ann Hummert, the king and queen of network soap operas, began to routinely include black doctors, teachers, and soldiers in their scripts. In addition, the federal government produced its own radio series, entitled Freedom's People, to dramatize the participation of African Americans in past wars, and it recruited Paul Robeson as a national and then international radio spokesman for the U.S. war effort. But at the end of the war, the government withdrew from the domestic broadcasting sphere, allowing the logic of the marketplace to reassert itself. Then with the advent of the new television networks, and their subsequent domination of the national broadcasting market, radio was forced to turn to local markets in order to survive as a commercial enterprise. Inadvertently, this led to the discovery of a "new Negro market" in regions where African Americans' numbers could no longer be ignored by broadcasters. This was especially the case in large urban centers, where nine out of ten black families owned radios by the late 1940s. The result of this convergence of economic necessity and a mushrooming listening audience was the emergence of black-appeal radio stations and the rise of the African-American disc jockeytwo interrelated developments that transformed the landscape of commercial radio in the postwar era.

A few black DJs were playing records over the airways in the 1930s; they worked through a brokerage system that charged them an hourly fee for airtime. The disc jockeys, in turn, solicited advertising aimed at the local black community and broadcast it in conjunction with recorded "race" music. Jack L. Cooper pioneered this approach in Chicago on his radio show The All Negro Hour, which first aired on WSBC in 1929. At first, he developed a live variety show with local black talent, but within two years he had switched to recorded music in order to cut costs. He played jazz discs, hosted a popular "missing persons" show, pitched ads, made community-service announcements, and also developed a series of weekend religious programs. This format was successful enough to make him into a millionaire; by the end of the 1930s, he had a stable of African-American DJs working for him on a series of black-appeal programs broadcast on two stations. In the 1940s Cooper was challenged as Chicago's premier black disc jockey by Al Benson, who also built up a small radio empire on local outlets with his own style of black-appeal programming. Cooper targeted the middle-class African-American audience; he played the popular big-band jazz recordings of the day and prided himself in speaking proper English over the air. Benson played the down-home blues of the era and spoke in the vernacular of the new ghetto populace, most of whom were working-class southern migrants. A new era of black radio was at hand.

By the end of the 1940s there was a growing number of aspiring DJs in urban black communities ready to take advantage of the new "Negro-appeal" formats springing up on stations throughout the country. In Memphis, Nat D. Williams was responsible for broadcasting the first African-American radio show there, on WDIA in 1948; he also created the station's new black-appeal format and launched the careers of numerous first-generation African-American DJs over WDIA's airways. Two of the most important were Maurice "Hot Rod" Hulbert, who moved on to become the dean of black disc jockeys in Baltimore, on WBEE; and Martha Jean "the Queen" Stienburg, who later became the most popular black DJ in Detroit, on WCHB. In 1950, WERD, in Atlanta, became the first African-American-owned radio station in the country when it was purchased by J. B. Blayton, Jr. He appointed his son as station manager and then hired Jack "the Rapper" Gibson as program director. Other black-appeal stations that came into prominence during the early 1950s included WEDR in Birmingham, Alabama; WOOK in Washington, D.C.; WCIN in Cincinnati; WABQ in Cleveland; KXLW in St. Louis; and KCKA in Kansas City, which became the second African-American-owned radio outlet in the nation in 1952. By 1956 more than four hundred radio stations in the United States were broadcasting black-appeal programming. Each of these operations showcased its own homegrown African-American disc jockeys, who were the centerpiece of the on-air sound.

The powerful presence and influence of the African-American DJs on the airways in urban America in the 1950s stemmed from two sources. On the one hand, they were the supreme arbiters of black musical tastes; they could make or break a new record release, depending on how much they played and promoted it. On the other hand, the black disc jockeys were also the new electronic griots of the black oral tradition, posturing as social rappers and cultural rebels. As such, they collectively constituted a social grapevine that was integral not just to the promotion of rhythm and blues but also to the empowerment of the growing civil rights movement in the South. Such black-appeal radio stations as WERD in Atlanta and WDIA in Memphis, as well as Al Benson's shows in Chicago, played a vital role in informing people about the early civil rights struggles. In a speech to black broadcasters late in his life, civil rights leader the Rev. Dr. Martin Luther King, Jr., paid special tribute to disc jockeys Tall Paul White (WEDR, Birmingham), Purvis Spann (WVON, Chicago), and Georgie Woods (WHAT, Philadelphia) for their important contributions to the civil rights efforts in their respective cities.

During the 1950s African-American radio DJs also had a profound effect on commercial radio in general. Some stationssuch as WLAC in Nashville, a high-powered AM outlet heard at night throughout the Southdevoted a hefty amount of their evening schedules to rhythm-and-blues records. In addition, the white disc jockeys at WLAC (John R., Gene Noble, Hoss Allen, and Wolfman Jack) adopted the on-air styles, and even dialect, of the black DJs. Many of their listeners, both black and white, thought that WLAC's disc jockeys were African Americans. This was also the case on WJMR in New Orleans, where the white DJs who hosted the popular Poppa Stoppa Show were actually trained to speak in black dialect by the creator of the show, an African-American college professor named Vernon Winslow. Other white DJs who became popular by emulating the broadcast styles of their black counterparts included Dewey Phillips in Memphis; Zenas "Daddy" Sears in Atlanta; Phil Mckernan in Oakland, California; George "Hound Dog" Lorenz in Buffalo, New York; and Allen Freed in Cleveland. Freed moved on to become New York City's most famous rock-and-roll disc jockey before his fall from grace as the result of payola scandals in the early 1960s.

Payola, the exchange of money for record airplay, was a common practice throughout the radio industry. It was an easy way for disc jockeys to supplement the low wages they were paid by their employers. Hence, many well-known black DJs were adversely affected by the payola exposés. Some lost their jobs when their names were linked to the ongoing investigations, and an unfortunate few were even the targets of income-tax-evasion indictments. The industry's solution to the payola problem was the creation of the "top forty" radio format, which in effect gave management complete control over the playlists of records to be aired on their stations. Formerly, the playlists had been determined by the individual DJs. This change led to the demise of both the white rock-and-roll disc jockeys and the black "personality" DJs associated with rhythm and blues, and then "soul" music. Black-appeal stations were centralized even further by the emergence of five soul radio chains in the 1960s, all of which were white-owned and -managed. By the end of the decade, these corporations controlled a total of twenty stations in key urban markets with large African-American populations, including New York, Chicago, Memphis, and Washington, D.C. The chain operations not only established standardized top-forty soul formats at their respective outlets, thus limiting the independence of the black DJs they employed, but they also eliminated most of the local African-American news and public-affairs offerings on the stations.

In spite of the trend toward top-forty soul formats, a number of black personality DJs managed to survive and even prosper in the 1960s. The most important were Sid McCoy (WGES, WCFL), Purvis Spann (WVON), and Herb Kent (WVON) in Chicago; LeBaron Taylor and Georgie Woods (both WDAS) in Philadelphia; Eddie O'Jay in Cleveland (WABQ) and Buffalo (WUFO); Skipper Lee Frazier (KCOH) in Houston; the Magnificent Montegue (KGFJ) in Los Angeles; and Sly Stone (KSOL) in San Francisco. LeBaron Taylor and Sly Stone went on to successful careers in the music industryTaylor as a CBS record executive and Stone as a pioneering pop musician. The Magnificent Montegue's familiar invocation, "Burn, baby, burn," used to introduce the "hot" records he featured on his show, inadvertently became the unofficial battle cry of the 1967 Watts rebellion. The new mood of black militancy sweeping the nation also found its way into the ranks of the African-American DJs, especially among the younger generation just entering the radio industry. Two of the more influential members of this "new breed," as they came to be known, were Del Shields (WLIB) in New York and Roland Young (KSAN, KMPX) in San Francisco. Both men independently pioneered innovative black music formats, mixing together jazz, soul, and salsa recordings.

The 1970s ushered in the current era of black-owned and -controlled radio operations, both stations and networks. In 1970, of the more than 300 black-formatted stations, only sixteen were owned by African Americans. During the next decade, the number of black-owned stations rose to 88, while the number of formatted stations surpassed 450. Some of the more prominent African Americans who became radio station owners during this era included entertainers James Brown and Stevie Wonder, Chicago publisher John Johnson, and New York City politician Percy Sutton. In particular, Sutton's Harlem-based Inner City Broadcasting (WLIB-AM, WBLS-FM) has been the national trendsetter in a black-owned and -operated radio from the early 1970s to the present. In 1977 African-American broadcasters organized their own trade organization, the National Association of Black-Owned Broadcasters. By 1990 there were 206 black-owned radio stations138 AM and 68 FMin the country.

It was also during the 1970s that two successful black radio networks were launched: the Mutual Black Network, founded in 1972, which became the Sheridan Broadcasting Network in 1979; and the National Black Network, started in 1973. Both of these operations provide news, talk shows, public affairs, and cultural features to their affiliate stations throughout the nation. In the 1980s the Sheridan network had more than one hundred affiliates and 6.2 million weekly listeners; in addition to news and public affairs, it offered a wide range of sports programming, including live broadcasts of black college football and basketball games. The National network averaged close to one hundred affiliates and four million weekly listeners in the 1980s; its most popular programs, in addition to its news reports, were journalist Roy Woods's One Man's Opinion and Bob Law's Night Talk. In 1991 Sheridan Broadcasting Corporation purchased National Black Network to form the American Urban Radio Network (AURN). As of 2005 AURN is the only African-Americanowned network radio company in the United States, broadcasting three hundred weekly news, entertainment, sports, and information programs to more than 475 radio stations that reach some twenty-five million listeners nationwide.

Two major formats have dominated black-owned commercial radio in the 1970s and 1980s"talk" and "urban contemporary." Talk radio formats emerged on African-American AM stations in the early 1970s; in essence they featured news, public affairs, and live listener call-in shows. By this time, the FM stations dominated the broadcasting of recorded music because of their superior reproduction of high-fidelity and stereo signals. The AM stations were left with talk by default. Inner City Broadcasting initiated the move toward talk radio formats among African-American stations when it turned WLIGAM, which it purchased in New York City in 1972, into "your total news and information station" that same year. The logic of the commercial radio market encouraged many of the other black AM operations, such as WOL-AM in Washington, D.C., to follow suit. Likewise, Inner City Broadcasting also pioneered the urban contemporary format on WBLS-FM during this same period. Much of the credit for the new format is given to Frankie Crocker, who was the station's program director at the time. To build up WBLS's ratings in the most competitive radio market in the country, Crocker scuttled the station's established jazz programming in favor of a crossover format featuring black music currently on the pop charts along with popular white artists with a black sound. The idea was to appeal to an upscale black and white audience. The formula worked to perfection; WBLS became the top station in the New York market, and scores of other stations around the country switched to the new urban contemporary format. One example was WHUR-FM, owned by Howard University in Washington, D.C. The station's original jazz and black-community-affairs format was sacked in favor of the urban contemporary approach in the mid-1970s. The new format allowed WHUR to become one of the top-rated stations in the Washington market. In the process, it gave birth to an innovative new nighttime urban contemporary style called "quiet storm," after the Smokey Robinson song of the same name. The architect of this novel format was Melvin Lindsey, a former Howard student and WHUR intern. In 1980 WOL-AM in Washington, D.C., was purchased by Catherine and Dewey Hughes. Catherine Hughes later bought out her now ex-husband's interest, and WOL-AM was the start of Radio One, Inc., the seventh-largest radio broadcasting company (as of 2003) to target African-American and urban listeners. Radio One owns and/or operates sixty-nine radio stations in twenty-two urban markets.

The 1970s and 1980s also marked the entrance of African Americans into the public broadcasting sphere. By 1990 thirty-two public FM stations were owned and operated by black colleges around the country, and another twelve were controlled by black community boards of directors. These stations are not subject to the pervasive ratings pressures of commercial radio, giving them more leeway in programming news, public affairs, talk, and unusual cultural features. Many of these stationssuch as WCLK-FM, owned by Clarke College in Atlanta; WSHAFM, owned by Shaw College in Raleigh, North Carolina; and WVAS-FM, from Alabama State University in Montgomeryhave adopted the jazz formats abandoned by African-American-owned commercial FM stations. Others, such as WPFW-FM in Washington, D.C. (the number one black public radio outlet in the country), have developed a more ambitious "world rhythms" format embracing the many musics of the African diaspora. In general, the growth of black public radio has expanded the variety and diversity of African-American programming found on the airways, while also increasing the numbers of African Americans working in radio.

However, since the passage of the 1996 Telecommunications Act, independent black radio stations have struggled to survive. The Telecom Act has allowed conglomerates in a single market to have radio holdings that receive up to 40 percent of the market's advertising revenue and has eliminated the forty-station nationwide ownership limit; broadcasters may purchase up to eight radio stations in large markets and five in small markets. This has led to a consolidation in which conglomerates, with greater financial resources, have benefited while black-owned stations with less capital have gone up for sale. According to the U.S. Department of Commerce, from 1995 to 1996 the number of black-owned FM stations dropped from 86 to 64 and AM radio stations from 109 to 101; in 1997 there were 169 minority-owned broadcasters but by 2001 the number was 149. The largest black-controlled radio broadcaster (and seventh-largest in the country), Radio One, owns 69 radio stations; in contrast, Clear Channel, the largest U.S. radio broadcaster, owned 1,200 stations as of 200376 of which targeted black and urban audiences. Single-station owners are going the way of the dodo, but various entrepreneurs are acquiring their own, albeit small, clusters of stations to maintain a presence within the industry by offering grassroots community appeal and diversity of programmingand marketing that programming to more than the African-American market in order to survive and grow.

See also Jazz; Minstrels/Minstrelsy; Rhythm and Blues; Robeson, Paul; Walker, George; Williams, Bert

Bibliography

Baraka, Rhonda. "American Urban Radio Networks." Billboard (October 13, 2001): 25.

Barlow, William. Voice Over: The Making of Black Radio. Philadelphia, Pa: Temple University Press, 1999.

Dates, Jannette, and William Barlow, eds. Split Image: African Americans in the Mass Media. Washington, D.C.: Howard University Press, 1989.

Dawkins, Walter. "Battle for the Airwaves!" Black Enterprise (May 2003): 6470.

Downing, John. "Ethnic Minority Radio in the USA." Howard Journal of Communication 1, no. 4 (1989): 135148.

Edmerson, Estelle. "A Descriptive Study of the American Negro in U.S. Professional Radio, 19221953." M.A. thesis, University of California at Los Angeles, 1954.

Ferretti, Frank. "The White Captivity of Black Radio." Columbia Journalism Review (summer 1970): 3539.

George, Marsha Washington. Black RadioWinner Takes All. Philadelphia, Pa: Xlibris Corp., 2002.

Jones, Charisse. "Owning the Airwaves." Essence (October 1998): 112120.

Tyson, Timothy B. Radio Free Dixie: Robert F. Williams and the Roots of Black Power. Chapel Hill: University of North Carolina Press, 1999.

Ward, Brian. Radio and the Struggle for Civil Rights in the South. Gainesville: University Press of Florida, 2004.

Williams, Gilbert A. Legendary Pioneers of Black Radio. West-port, Conn.: Praeger Publishers, 1998.

william barlow (1996)

christine tomassini (2005)

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Radio

Radio ★★½ 2003 (PG)

Feelgooder inspired by the true story of the mentally disabled James “Radio” Kennedy (Gooding Jr.), who befriends the kindly local football coach (Harris) and becomes a beloved mascot of sorts in Anderson, South Carolina circa 1976. Coach Jones finds Radio (so named for his ample, muchloved collection of discarded radios) locked in a storage shed after being taunted by a few players and is determined to help him. Radio, in turn, ends up teaching the town a lesson or two about the Golden Rule. Top notch cast and script can't completely save the somewhat saccharine but nonetheless inspirational story. Based on a Sports Illustrated story by Gary Smith. 109m/C VHS, DVD . US Cuba Gooding Jr., Ed Harris, Alfre Woodard, S. Epatha Merkerson, Chris Mulkey, Sarah Drew, Riley Smith, Patrick Breen, Brent Sexton, Debra Winger; D: Mike Tollin; W: Mike Rich; C: Don Burgess; M: James Horner.

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Radio

Radio

EARLY EXPERIMENTATION
RADIO GOES HOLLYWOOD
CROSSOVER CAREERS
AFTER TV
FURTHER READING

Hollywood's involvement with radio predates the movies' ability to talk. From the earliest years of broadcasting, farsighted film producers and studio heads saw in radio a promotional medium made to order for enhancing the popular reach and appeal of their valuable entertainment empires. As sound film debuted and brought members of the "radio trust"—RCA and AT&T—into closer connection with film operations, several major studios made countermoves into the business of network radio. Though largely excluded from network ownership, the studios formed an alliance with the advertising agencies, which by the mid-1930s were producing the bulk of commercial programs on the air. "Prestige" radio production had moved to Hollywood by the late 1930s, and the lively process of mutual influence and exchange enriched both industries, setting the stage for Hollywood's increasing domination of television beginning in the late 1950s. Yet even as television took over the entertainment genres and cultural functions that had been created by network radio, the film industry, by expanding into other areas of media production and distribution, remained a player in the radio business. In the twenty-first century, all five major over-the-air television networks (NBC/Universal, CBS/Viacom/Paramount, ABC/Disney, Fox, and CW [formerly WB and UPN] as well as the majority of cable channels either bear a studio's name or are part of a filmmedia conglomerate. Producers, writers, directors, stars, and properties flow seamlessly from one medium to the other. This process began in radio.

EARLY EXPERIMENTATION

In the days before regulatory and network standardization, when the main business of radio was inviting various representatives of entertainment businesses on the air to publicize themselves, it seemed natural that Hollywood, with its immense reservoirs of talent under contract, should join in to publicize that other "national" medium, the cinema. One of the earliest cases of filmradio cooperation took place not in Hollywood but on the stage of the Capitol Theater in New York City, part of the Loew's/MGM chain. In 1923 theater manager Samuel L. Rothafel entered into an agreement with the American Telephone and Telegraph Corporation (AT&T) to broadcast his prefilm stage show over the new station WEAF. The results were so positive that it quickly became a regular feature, called Roxy and His Gang, one of the earliest hits of radio broadcasting. Soon other movie theaters jumped on the bandwagon.

Many big-city theaters featured elaborate stage shows and enormous theater organs, whose musical accompaniments animated their film showings. Concerts by theater organists were broadcast over WMAC, WGN, and KWY in Chicago and in many other cities starting in 1925. In 1925 Harry Warner of Warner Bros. put forth a prediction and a challenge:

I am in favor of the motion picture industry, after the wave-length situation has been adjusted (as it will be)—building and maintaining its own broadcasting stations in New York and Los Angeles, and possibly in the Middle West. Through these sources … programs could be devised to be broadcast before and after show hours, tending to create interest in all meritorious pictures being released or playing at that time. Nights could be assigned to various companies, calling attention to their releases and advising where they were playing in that particular locality. Artists could talk into the microphone and reach directly millions of people who have seen them on the screen but never came in contact with them personally or heard their voices. Such programs would serve to whet the appetites of the radio audience and make it want to see the persons they have heard and the pictures they are appearing in.
(Motion Picture World, 11 April 1925)

Warner followed up on this vision by opening up station KFWB in Los Angeles that same year, and a second one, WBPI, in New York City in 1926. In the summer of 1926, Sam Warner took a portable transmitter on a cross-country tour, broadcasting from theaters showing Warner Bros. films.

By 1927 the major studios could see the sound era rapidly approaching. Earlier, they had jointly agreed to a "stand still" position, in order to see whether the RCA or the AT&T sound system would predominate. Either way, Hollywood studios would in effect find themselves in technical thrall to the interests behind NBC, at this point (with CBS still struggling to get organized) the only broadcasting network with national reach. RCA was NBC's parent company; AT&T had an exclusive arrangement with NBC for the provision of landlines, the backbone of network broadcasting. Simultaneously, regulators in Washington were working on passage of the Radio Act of 1927, which promised a reorganization of the radio spectrum with an express mandate to bring the "chaos" of radio under control. Studios increased the pace of radio experimentation, attempting to get a foot-hold in the promising new business before restrictions might potentially be imposed, either by Washington or by contractual limitations from sound-on-film technology providers.

In May 1927 Paramount announced plans to form the Keystone Network, in partnership with the Postal Telegraph Company, one of AT&T's only competitors, "for dramatizing and advertising first-run motion pictures." As a backup plan, Paramount head Adolph Zukor also approached the interests behind the proposed NBC competitor, United Independent Broadcasters (later to become CBS) to suggest a partnership that he proposed might be renamed the Paramount Broadcasting System. In September MGM announced an ambitious project with the Loew's theater chain: a planned network based on movie materials and promotion that would link over sixty stations in more than forty cities. In December, to give audiences a taste of things to come, MGM experimented with the world's first "telemovie": a dramatic, blow-by-blow account of Love (1927), MGM's adaptation of Tolstoy's Anna Karenina starring Greta Garbo and John Gilbert, delivered on-air by WPAP's announcer Ted Husing (usually known for his sports coverage) as it unreeled before his eyes in the Embassy Theater in New York. Despite much excitement in the industry, neither the Keystone Chain, the Paramount Broadcasting System, nor the Loew's/MGM network reached fruition. A combination of regulatory discouragement, exhibitor opposition, and competition from other sources diverted studios' radio ideas in other directions.

Upon the expiration of the "stand still" agreement in 1928, film studios jointly decided to go with AT&T subsidiary Western Electric's sound technology. Left out in the cold, RCA in 1929 formed its own studio, RKO Pictures, and ushered in the era of film-radio cooperation in earnest as RKO and NBC learned to share talent and properties, such as the RKO Theater of the Air. Faced with this unsettling prospect, in the summer of 1929, just months before the stock market crash, Paramount again approached CBS. A stock transfer was hammered out, by the terms of which Paramount received a 49 percent interest in CBS while CBS received a certain number of Paramount shares. In three years Paramount would have the option of either buying the rest of CBS or simply regaining its own stock by turning back CBS's. By 1932, however, the country was in the depths of the Depression, and while radio's fortunes continued upward, the film industry was in steep decline. Rather than further consolidate their mutual interests, Paramount withdrew its merger offer, and the brief alliance was over. RCA divested itself of most of its interest in RKO in the late 1930s under similar pressures. Studios would not attempt to enter networking again until the television era.

RADIO GOES HOLLYWOOD

As the Depression continued, film industry profits suffered as theaters went out of business and box-office receipts slowed to a trickle. Radio, however, continued to thrive. As advertising agencies began to take the broadcast medium seriously as an outlet for their customers' campaigns, a new and influential partnership was about to emerge. Dissatisfied with CBS and NBC's staid approach to programming, several aggressive advertising firms turned their attention to Hollywood's untapped potential for radio-based product promotion. One of the biggest players in this Hollywood-agency alliance was the J. Walter Thompson Company (JWT), whose plan for radio advertising envisioned big-budget, starstudded productions sponsored by JWT clients over the major radio networks. By the mid-1930s JWT was producing at least five shows out of each year's top ten, most of them featuring Hollywood talent, such as The Chase and Sanborn Hour (with Edgar Bergen and Charlie McCarthy), Rudy Vallee's Fleischmann Yeast Hour, and Lux Radio Theatre. Other major agencies included Young and Rubicam, Blackett-Sample-Hummert, and Dancer Fitzgerald. When in 1936 AT&T, as a result of an investigation by the FCC, reduced its land line rates to the West Coast, a "rush to Hollywood" resulted, and most major agencies along with the two national networks opened up studios in Los Angeles. Radio had gone Hollywood.

This productive and profitable association would have great impact on both the radio and film industries. A variety of radio programs developed that centered on movie industry stars, properties, and Hollywood celebrities. The most prestigious was the movie adaptation format pioneered by JWT's Lux Radio Theatre. Hosted by celebrity director Cecil B. DeMille (1881–1959), Lux presented hour-long radio adaptations of recent Hollywood film releases, introduced and narrated by DeMille and featuring well-known film stars. Others in this format, often referred to at the time as "prestige drama," included The Screen Guild Theater, Hollywood Premiere, Academy Award Theater, Dreft Star Playhouse, Hollywood Startime, and the Screen Directors' Playhouse. A popular feature of these programs was the intimate, casual interviews with famous stars; DeMille, for instance, would chat at the end of each show with that night's leading actors, often casually working in a mention of the sponsor's product. Here audiences could enjoy a new, more intimate relationship with stars and celebrities that had formerly been available only in the pages of fan magazines. Chatting about their upcoming pictures, a recent performance experience, or even domestic details and romantic tidbits, allowed the celebrity to step off the screen and into the familiar space of the living room.

The second major venue for Hollywood stars and film promotion was radio's leading genre, the big-name variety show. Fleischmann Yeast Hour, The Jack Benny Program, The Fred Allen Show, and many others featured regular guest appearances from Hollywood's A-list stars, often promoting their latest pictures or acting out skits related to film properties. Supporting roles were often filled by B-list actors and actresses, some of whom went on to considerable broadcast fame. Many stars eventually began hosting such programs themselves, especially in the late 1930s and early 1940s. Adolph Menjou and John Barrymore served as hosts for The Texaco Star Theater; Al Jolson appeared on radio almost exclusively after 1935; William Powell and Herbert Marshall hosted Hollywood Hotel at various times.

Some directors got into the act as well. Orson Welles's dramatic radio debut in 1938 on The Mercury Theatre on the Air, most notably his 30 October broadcast of War of the Worlds, helped secure his contract with RKO to produce, among other films, Citizen Kane (1941). Welles would frequently return to radio, as a variety show guest, guest host, and producer of lesserknown programs. Many accounts of the Mercury Theatre on the Air years agree that, once the first couple of broadcasts were past, the group Welles had gathered around him—notably John Houseman and Howard Koch—actually did most of the dramatic selection and adaptation work; nevertheless Welles's inimitable sense of drama and timing as well as his penchant for reflexive and confrontational material permeated the productions. And Welles would bring a heightened awareness of the potential of sound as an expressive medium with him to Citizen Kane and much of his other film work. Alfred Hitchcock, too, established a reputation on American radio, as well as film, before becoming a television personality.

CROSSOVER CAREERS

Many Hollywood stars extended their careers on radio, some of them also moving into television in its early years. Groucho Marx made frequent appearances not only on comedy-variety programs but on the rising genre of humorous quiz shows. In 1947 he became the host of ABC radio's popular You Bet Your Life, which made the transition to television in 1950 and ran until 1957. Ed Wynn started out in film, moved to radio and television, then played comic parts in a series of films in the 1950s and 1960s. Robert Young became established as a reliable second leading man in the 1930s and 1940s, then debuted the long-running Father Knows Best franchise on radio, before moving to television. Especially for Hollywood's extensive B-list starts, radio in the late 1940s became a springboard both to television fame and, less frequently, back toward greater eminence in the film business.

It was a set of Hollywood's secondary ladies who made the deepest mark on one of broadcasting's most enduring genres, the situation comedy, first on radio, then on television. Such B-list performers and comediennes as Lucille Ball, Dinah Shore, Joan Davis, Eve Arden, Hattie McDaniel, and Ann Sothern began by building up reputations as frequent radio guest stars in the 1930s and early 1940s. When World War II removed many male comedians from the air, as well as increasing the prominence and importance of the female audience at home, the film industry supplied key talent to move into prime time. Out of this conjunction the sitcom was born, taking comedy in a new direction—away from the stand-up, gag-based variety format and toward a new genre based on recurring characters in humorous situations, emphasizing domestic settings.

Joan Davis was the first to step into the leading-lady spotlight, as she moved from a supporting cast position on The Rudy Vallee Show in 1941 to primary status when Vallee left the program to go into the military in 1943. Renamed The Sealtest Village Store, it featured Davis as a frustrated, man-chasing spinster; she would go on to take the headline role in The Joan Davis Show on CBS in 1945, and from there to television in the sitcom I Married Joan (NBC, 1952–1955). Lucille Ball, the best-known of radio's film comediennes, moved, like Davis, from an RKO contract to star in My Favorite Husband (CBS, 1948–1951), though her fame came with the debut of I Love Lucy in 1950 on CBS-TV. Ann Sothern took her fame as the star of MGM's Maisie films to radio in a situation comedy of the same name in 1949; she went on to star in television sitcoms for the next twelve years. Eve Arden, who starred in a long line of B-movies from the 1920s through the 1940s, including a series of Republic Studios features based on the Lucky Strike Your Hit Parade radio series, debuted as Our Miss Brooks on CBS in 1948. Hattie McDaniel, the first African American actress to win an Emmy, for her role in Gone with the Wind (1939), made her radio headliner debut in the long-running Beulah in 1947. These pioneering woman-centered situation comedies used the star power of their Hollywood-based leading ladies to draw ever larger audiences to this new form, and to take them from radio to television in the early 1950s.

Other properties moved from film to radio, many of them adaptations from fiction or comics. Dashiell Hammett's The Thin Man first mutated into a series of films starring William Powell and Myrna Loy beginning in 1937; it became a radio program in 1941 and later shifted to television. Series like The Lone Ranger and The Green Hornet prospered in film, radio, and television formats. The film industry also came to increasingly rely on the star-producing capabilities of radio, with radio personalities starring in many popular Hollywood films. One of the first of these crossovers was Check and Double Check for RKO (1930), starring Freeman Gosden and Charles Correll as the characters they played in the Amos 'n' Andy show on radio. Movies like The Big Broadcast of 1936—and 1937 and 1938—were produced specifically to consolidate radio stars' popularity with the film-viewing public, and to cement the Hollywood-radio relationship. Other stars who had first made it big on radio found significant new success in films, like the "Road" pictures starring Bing Crosby, Bob Hope, and Dorothy Lamour (Road to Zanzibar [1941], Road to Morocco [1942], Road to Rio [1947], et al.). Rudy Vallee, Eddie Cantor, and Jack Benny all met with box-office success in films that often highlighted their roles as radio stars and featured the exciting world of radio behind the scenes. This tradition continued, as Howard Stern's 1997 movie about his radio career, Private Parts, attests. Other memorable films about radio and its role in American life include The Hucksters (1947), an indictment of advertising-dominated radio and its effects on American postwar society; George Lucas's classic American Graffiti (1973), with its memorable top-40 soundtrack and a cameo by the legendary DJ Wolfman Jack; and Woody Allen's Radio Days (1987), a highly nostalgic look at life before television.

AFTER TV

Although the nature of radio changed dramatically once TV came onto the scene, some studios did maintain a persistent presence in radio ownership and production. Warner Bros., Paramount, RKO, and MGM all owned radio stations, and also got in on television station ownership early. MGM went into syndicated radio program production and distribution in the late 1940s, with such programs as The MGM Theater of the Air and Maisie. Just as film companies diversified into television, they also began to acquire interests in the music industry, the new backbone of radio. For example, the Disney Corporation holds extensive interests in music recording, and through its merger with ABC in 1995 came to own radio stations that reach 24 percent of US households. Twentieth Century Fox was purchased by Rupert Murdoch's News Corporation in the 1980s and is now linked with satellite music channels worldwide. News Corp. also owns the Australian Mushroom and Festival record labels. And in this age of synergy, the tie between movies and music has become tighter than ever before, with movie soundtracks used to promote artists and recordings, and soundtrack releases often achieving billions in sales.

In the era of new media, where the lines between film, radio, television, music, recordings, and the Internet seem to be growing blurrier every day, the integrated entertainment corporations formerly designated by the term "Hollywood" have fingers in nearly every form of media that reaches into the home—or anywhere the viewer might be. Now Internet radio technology gives companies the ability to go online with their own "radio" services. DisneyRadio.com already provides a schedule of music and features from its films and artists, oriented toward children. Television shows on studio-owned networks promote recordings distributed by the company's record arm, which become hits on pop radio. Recording stars launch film careers; film and television stars, like Janeane Garofalo and Al Franken, start radio careers. Although in the United States the days of radio drama and comedy faded long ago, transferring their stars and audiences to television, the film industry continues to play a vital behind-the-scenes role linking radio to a host of other media. Without Hollywood, American radio could never have risen to the heights of creativity and popularity it achieved in its heyday. Without radio, Hollywood as we know it today would be missing some of its brightest lights and most memorable ingredients. The twenty-first century's digital media promise to bring these two media venues into an ever closer relationship.

SEE ALSO Sound;Technology;Television

FURTHER READING

Dunning, John. On the Air: The Encyclopedia of Old-Time Radio. New York: Oxford University Press, 1998.

Gomery, Douglas. "Toward an Economic History of the Cinema: The Coming of Sound to Hollywood." In The Cinematic Apparatus, edited by Stephen Heath and Teresa de Lauretis, 38–46. New York: St. Martin's Press, 1982.

Hilmes, Michele. "Femmes Boff Program Toppers: Women Break into Prime Time, 1943–1948." In Transmitting the Past: Historical and Cultural Perspectives on Broadcasting, edited by Susan Brinson and J. Emmett Winn, 137–160. Tuscaloosa: University of Alabama Press, 2004.

——. Hollywood and Broadcasting: From Radio to Cable. Urbana: University of Illinois Press, 1990.

Jewell, Richard B. "Hollywood and Radio: Competition and Partnership in the 1930s." Historical Journal of Film, Radio and Television 4, no. 2 (1984): 125–141.

Lucich, Bernard. "The Lux Radio Theatre." In American Broadcasting: A Sourcebook on the History of Radio and Television, edited by Lawrence W. Lichty and Malachi C. Topping, 391–393. New York: Hastings House, 1975.

Rothafel, Samuel L. Broadcasting: Its New Day. New York: Century, 1925.

Smoodin, Eric. "Motion Pictures and Television, 1930–1945." Journal of the University Film and Video Association (Summer 1982): 3–18.

Michele Hilmes

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Radio

Radio

The history of radio

Radio and the electromagnetic spectrum

How radio signals are created

Modulation

Demodulation

Wavelengths, frequencies, and antennas

Radio signals and energy

Radio signal propagation

Shortwave radio

Regulation of radio transmissions

The future of radio

Resources

Radio is the transmission and reception of long-wavelength electromagnetic waves. Radio makes it possible to establish wireless one-way or two-way communication between transmitters and receivers. Radio signals can carry speech, music, telemetry, or digitally-encoded entertainment. They also occur naturally throughout the universe. Cordless telephones and wireless computer components use low-power radio transmitters and receivers to connect without wires. Cellular telephones use a network of computer-controlled low power radio transmitters to enable users to place telephone calls away from phone lines.

The history of radio

In the nineteenth century, in Scotland, James Clerk Maxwell (18311879) described the theoretical basis for radio transmissions with a set of four equations known ever since as Maxwells field equations. Maxwell was the first scientist to use mechanical analogies and powerful mathematical modeling to create a successful description of the physical basis of the electromagnetic spectrum. His analysis provided the first insight into the phenomena that would eventually become radio. He deduced correctly that the changing magnetic field created by accelerating charge would generate a corresponding changing electric field. The resulting changing electric field would, he predicted, regenerate a changing magnetic field in turn, and so on. Maxwell showed that these interdependent changing electric and magnetic fields would together be a part of a self-sufficient phenomenon required to travel at the speed of light.

Not long after Maxwells remarkable revelation about electromagnetic radiation, Heinrich Hertz (18571894) demonstrated the existence of radio waves by transmitting and receiving a microwave radio signal over a considerable distance. Hertzs apparatus was crude by modern standards but it was important because it provided experimental evidence in support of Maxwells theory.

Guglielmo Marconi (18741937) was awarded the Nobel Prize in physics in 1909 to commemorate his development of wireless telegraphy after he was able to send a long-wave radio signal across the Atlantic Ocean.

The first radio transmitters to send messages, Marconis equipment included, used high-voltage spark discharges to produce the charge acceleration needed to generate powerful radio signals. Spark transmitters could not carry speech or music information. They could only send coded messages by turning the signal on and off using a telegraphy code similar to the land-line Morse code.

Spark transmitters were limited to the generation of radio signals with very-long wavelengths, much longer than those used for the present AM-broadcast band in the United States. The signals produced by a spark transmitter were very broad with each signal spread across a large share of the usable radio spectrum. Only a few radio stations could operate at the same time without interfering with each other. Mechanical generators operating at a higher frequency than those used to produce electrical power were used in an attempt to improve on the signals developed by spark transmitters.

A technological innovation enabling the generation of cleaner, narrower signals was needed. Electron tubes provided that breakthrough, making it possible to generate stable radio frequency signals that could carry speech and music. Broadcast radio quickly became established as a source of news and entertainment.

Continual improvements to radio transmitting and receiving equipment opened up the use of successively higher and higher radio frequencies. Short waves, as signals with wavelengths less than 200m are often called, were found to be able to reach distant continents. International broadcasting on shortwave frequencies followed, allowing listeners to hear programming from around the world.

The newer frequency-modulation system, FM, was inaugurated in the late 1930s. For more than 25 years it struggled for acceptance, but it eventually became the most important method of domestic broadcast. FM offers many technical advantages over AM, including almost complete immunity to the lightning-caused static that plagues AM broadcasts. The FM system improved the sound quality of broadcasts, far exceeding the fidelity of the AM radio stations of the time. The FM system was the creation of E. H. Armstrong, perhaps the most prolific inventor among all those who made radio possible.

In the late 1950s, stereo capabilities were added to FM broadcasts along with the ability to transmit additional programs on each station that could not be heard without a special receiver. A very high percentage of FM broadcast stations today carry these hidden programs that serve special audiences or markets. This extra program capability, called SCA for Subsidiary Communications Authorization, can be used for stock market data, pager services, or background music for stores and restaurants.

Radio and the electromagnetic spectrum

Radio utilizes a small part of the electromagnetic spectrum, the set of related wave-based phenomena that includes radio along with infrared light, visible light, ultraviolet light, x rays, and gamma rays. Picture the electromagnetic spectrum as a piano keyboard: radio will be located where the piano keys produce the low frequency musical notes. Radio waves have lengths from many miles down to a fraction of a foot.

Radio waves travel at the velocity of electromagnetic radiation. A radio signal moves fast enough to complete a trip around the earth in about 1/7 second.

How radio signals are created

Jiggle a collection of electrons up and down one million times a second and a 1-megahertz radio signal will be created. Change the vibration frequency and the frequency of the radio signal will change.

Radio transmitters are alternating voltage generators. The constantly changing voltage from the transmitter creates a changing electric field within the antenna. This alternating field pushes and pulls on the conduction electrons in the wire that are free to move. The resulting charge acceleration produces the radio signal that moves away from the antenna. The radio signal causes smaller sympathetic radio frequency currents in any distant electrical conductor that can act as a receiving antenna.

Modulation

A radio signal by itself is like a mail truck without letters. A radio signal alone, without superimposed information, is called a carrier wave. An unmodulated radio signal conveys only the information that there was once a source for the signal picked up by the receiver. Adding information to a carrier signal is a process called modulation. To modulate a radio carrier means that it is changed in some way to correspond to the speech, music, or data it is to carry.

The simplest modulation method is also the first used to transmit messages. The signal is turned on and off to transmit the characters of an agreed code. Text messages can be carried by the signal modulated in this way. unique patterns stand for letters of the alphabet, numerals, and punctuation marks.

The least complicated modulation method capable of transmitting speech or music varies the carrier signals instantaneous power. The result is called amplitude modulation, or AM. Another common system varies the signals instantaneous frequency at an informational rate. The result is frequency modulation, FM.

If radio is to transmit speech and music, information must be carried that mimics the pattern of changing air pressure the ear would experience hearing the original sound. To transmit sounds these air-pressure changes are converted into electrical signals, amplified electronically, then used to modulate the carrier.

Amplitude modulation was the first process to have the capability of transmitting speech and varied the radio signals instantaneous power at a rate that matched the original sound vibrations in the air. A better modulation technology followed that varied the instantaneous frequency of the radio signal but not the amplitude. Frequency modulation, or FM, has advantages compared to AM but both AM and FM are still in use.

Sound can be converted to digital data, transmitted, then used to reconstruct the original waveform in the receiver. It seems likely that a form of digital modulation will eventually supplant both FM and AM.

Demodulation

Radio receivers recover modulation information in a process called demodulation or detection. The radio carrier is discarded after it is no longer needed. The radio carriers cargo of information is converted to sound using a loudspeaker or headphones or processed as data.

Wavelengths, frequencies, and antennas

Each radio signal has a characteristic wavelength just as is the case for a sound wave. The higher the frequency of the signal, the shorter will be the wavelength. Antennas for low- frequency radio signals are long. Antennas for higher frequencies are shorter, to match the length of the waves they will send or receive.

It is a characteristic of all waves, not just radio signals, that there is greater interaction between waves and objects when the length of the wave is comparable to the objects size. Just as only selected sound wavelengths fit easily into the air column inside a bugle, only chosen frequencies will be accepted by a given antenna length. Antennas, particularly transmitting antennas, function poorly unless they have a size that matches the wavelength of the signal presented to them. The radio signal must be able to fit on the antenna as a standing wave. This condition of compatibility is called resonance. If a transmitter is to be able to feed energy into an antenna, the antenna must be resonant or it will not take power from the transmitter. A receiver antenna is less critical, since inefficiency can be compensated by signal amplification in the receiver, but there is improvement in reception when receiving antennas are tuned to resonance.

If an antennas physical length is inappropriate, capacitors or inductors may be used to make it appear electrically shorter or longer to achieve resonance.

Near 100 MHz, near the center of the FM broadcast band in most of the world, signals have a wavelength of approximately three meters. At 1 MHz, near the center of the U.S. AM broadcast band, the signals wavelength is 327 yards (300 m), about three times the length of a football field. One wavelength is about 1 ft (0.3 m) at the ultra-high frequency used by cellular telephones.

Radio signals and energy

Energy is required to create a radio signal. Radio signals use the energy from the transmitter that accelerates electric charge in the transmitting antenna. A radio signal carries this energy from the transmitting antenna to the receiving antenna. Only a small fraction of the transmitters power is normally intercepted by any one receiving antenna, but even a vanishingly-small received signal can be amplified electronically millions of times as required.

Radio signal propagation

Radio signals with very short wavelengths generally follow straight line paths much as do beams of light, traveling from transmitter to receiver as a direct wave. Radio signals with very long wavelengths follow the curvature of Earth, staying close to the surface as signals called ground waves.

Radio signals with intermediate wavelengths often reflect from layers of electrically-charged particles high above Earths surface. These signals are known as skywaves. The layers of electrically-charged particles found between 25-200 mi (40322 km) above Earth are collectively known as the ionosphere. The ionosphere is renewed each day when the suns radiation ionizes atoms in the rarefied air at this height. At higher altitudes the distance between ions causes the ionization to persist even after the sun sets.

A good way to become familiar with radio propagation is to listen for distant AM-broadcast radio at various times of the day. A car radio works well for this experiment because they often have better sensitivity and selectivity than simpler personal radios.

During the daylight hours, on the standard-broadcast band, only local stations will normally be heard. It is unlikely that you will hear stations from more than 150 mi (241 km). As the sun sets you will begin to hear signals from greater distances.

AM-broadcast reception is generally limited to ground-wave radio signals when the sun is high in the sky. There is a very dense layer of the ionosphere at a height of approximately 25 mi (40 km) that is continually created when the sun is high in the sky. This D layer, as it is called, absorbs medium wavelength radio signals so that skywave signals cannot reflect back to earth. The D layer dissipates quickly as the sun sets because the suns rays are needed to refresh the ionization of this daytime-only feature of the ionosphere. After dark, when the D layer has disappeared, you will hear strong signals from far away cities.

After the D layer has disappeared, skywave signals reflect from a much higher layer of the ionosphere called the F layer. The F layer acts as a radio mirror, bouncing skywaves back to earth far from their source. The F layer degrades in darkness as does the D layer, but since the ions are separated more widely at higher altitude, the F layer functions as a significant radio mirror until dawn. Toward morning stations at intermediate distances fade, leaving only skywave signals that reflect from the thinning ionosphere at a very shallow angle.

Signal absorption by the D layer is less at shorter wavelengths. Stations using higher frequencies can use skywave in the daytime. High frequencies pass through the D layer. Skywave radio circuits are usually best in the daytime for higher frequencies, just at the time that the standard-broadcast band is limited to groundwave propagation.

Forecasting long distance radio signal propagation conditions depends upon predicting conditions on the sun. It is the changing radiation from the sun that affects long distance radio circuits when the ionosphere changes as Earth rotates. On the sunlit side of Earth the ionosphere is most strongly ionized. On the night side of Earth the radio ionosphere begins to dissipate at sunset until it is almost insignificant as a radio mirror in the early morning hours. When the ionosphere is at its best as a reflector it can support communication between any locations on Earth.

When the ionosphere is more densely ionized it will reflect radio signals with a shorter wavelength than when the ionization is weaker. At any one time, between any two distant locations on Earth, there is a limiting upper frequency that can be used for radio communication. Signals higher in frequency than this maximum-usable frequency, F layer called the MUF, pass through the ionosphere without returning to earth. Slightly lower than the MUF, signals are reflected with remarkable efficiency. A radio signal using less power than a flashlight can be heard on the opposite side of Earth just below the MUF. The MUF tends to be highest when the sun is above the midpoint between two sites in radio communication.

The 11-year solar sunspot cycle has a profound effect on radio propagation. When the average number of sunspots is large, the sun is more effective in building the radio ionosphere. When the suns surface is quiet the maximum-usable frequency is usually very low, peaking at less than half the MUF expected when the sun surface is covered with sunspots.

From time to time, the sun bombards Earth with charged particles that disrupt radio transmissions. When solar flares are aimed toward Earth, the earths magnetic field is disturbed in a way that can cause an almost complete loss of skywave radio propagation. Microwave radio signals are not significantly disturbed by the magnetic storms since microwaves do not depend upon ionospheric reflection.

FM-broadcast signals are seldom heard reliably further than the distance to the horizon. This is because the frequencies assigned to these services were deliberately chosen to be too high to expect the ionosphere to reflect them back to earth. FM signals are received as direct waves, not skywaves. The limited range of FM stations is an advantage because frequency assignments can be duplicated in cities that are in fairly close proximity without encountering unacceptable interference. This protection is much harder to achieve where skywave propagation may permit an interfering signal to be heard at a great distance.

KEY TERMS

Antenna An electrical conductor used to send out or receive radio waves.

Capacitor Electrical component that cancels magnetic property of wire.

D Layer Arbitrary designation for the lowest layer of the ionosphere.

Electric field The concept used to describe how one electric charge exerts force on another, distant electric charge.

Electron tube Active device based on control of electrons with electric fields.

F layer Arbitrary designation for the highest layer of the ionosphere.

Gamma ray Electromagnetic radiation with the shortest wavelengths.

Inductor Electrical component that adds magnetic property to wire.

Infrared light Light with wavelengths longer than those of visible light.

Ionized Missing one or more electrons, resulting in a charged atom.

Magnetic field Effect in space resulting from the motion of electric charge.

MegaHertz One million cycles per second; MHz.SI abbreviation for MegaHertz.

Morse code Dot and dash code used to send messages over telegraph wires.

Resonance The enhancement of the response of a system to a force, when that force is applied at a particular frequency known as the resonant frequency.

Selectivity Receiver property enabling reception of only wanted signals.

Sensitivity Receiver property enabling reception of weak signals.

Standing wave A stationary pattern of activity resulting from interference.

Sunspot Cooler and darker areas on the surface of the Sun. They appear dark only because they are cooler than the surrounding surface. Sunspots appear and disappear in cycles of approximately 11 years.

Telemetry Engineering and scientific measurements transmitted by radio.

X ray Electromagnetic radiation of very short wavelength, and very high energy.

Shortwave radio

Shortwave radio services may change frequency often as the ionospheres reflectivity varies. Unlike domestic broadcast stations that stay on a single assigned frequency, shortwave broadcast stations move frequency to take advantage of hour-to-hour and season-to-season changes in the ionosphere. As the 11-year sunspot cycle waxes and wanes, shortwave stations throughout the world move to shorter wavelengths when there are more sunspots and to longer wavelength bands when sunspots are minimal.

Listening to shortwave radio requires more effort than listening to local domestic radio. The best frequencies to search change from one hour to the next throughout the day. Due to the effect of the sun, shortwave signals sometimes may disappear for days at a time, then reappear with astounding strength. Many shortwave stations do not broadcast at all hours of the day. In addition, a station must be targeting your part of the world specifically; otherwise the signal will probably be weak.

Regulation of radio transmissions

The part of the electromagnetic spectrum that can be used for radio communication cannot accommodate everyone who might wish to use this resource. Access is controlled and technical standards are enforced by law. With few exceptions, radio transmissions are permitted only as authorized by licenses.

Since 1934 in the United States, licensing and equipment approval has been the responsibility of the Federal Communications Commission. Similar regulation is the rule in other countries. Technical standards are required by radio regulation. Just as traffic laws improve highway safety, laws and regulations that encourage the fair use of the limited radio spectrum help to avoid conflicts between users.

The future of radio

Radio broadcasting now includes a digital system known as DAB (digital audio broadcasting) that an achieve compact-disc quality in radio reception. Recent innovations in satellite radio systems allow radio programming to be beamed into space where it is processed by orbiting satellites that then widely disseminate a return signal toward the ground. Users of special receivers that can decode the satellite systems can thus enjoy programming thousands of miles from the source (ground broadcasting stations are also used to ensure quality reception in urban areas where building might inhibit reception of signal from the satellite. The digitized audio signal is so much lower in power than the main programming that it is inaudible to listeners with standard analog receivers.

Resources

BOOKS

American Radio Relay League. The ARRL Handbook for Radio Communications 2007. Newington, CT: American Radio Relay League, 2006.

Someda, Carlo G. Electromagnetic Waves. 2nd ed. Boca Raton, FL: CRC, 2006.

Donald Beaty

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Radio

Radio

One of the most influential technological advances of the early twentieth century was the radio. Basic radio technology had been around for several decades, but it was not until the 1920s that people bought and kept radios in their homes just for entertainment purposes. In 1920 Frank Conrad (1874–1941), an engineer at the Westinghouse company, began broadcasting music from his home radio. This led to America's first radio station, KDKA.

By the end of 1922, more than five hundred radio stations were in operation. Consumers spent $400 million on radios in 1925, four times the amount spent on them in 1920. Radio broadcasting had a major impact on American culture.

Radio stations expanded their programs to include more than just music. Sports coverage was especially popular, as announcers brought play-by-play accounts of baseball games to listeners. Boxing was the other popular sport of the decade, and listeners received blow-by-blow reports of the matches as they happened.

As the public's interest in sports and music increased, so did interest in variety and comedy shows. Typical segments included the latest jazz tunes, opera selections, lectures, drama, and comedy skits. The comedy show Amos and Andy was particularly popular.

Radio became increasingly important to politics in the 1920s. For the first time, politicians were able to reach a wide segment of the population without having to travel to various cities and towns across the country. Calvin Coolidge (1872–1933; served 1923–29) was the first U.S. president to broadcast on the radio. By the time he left office, he had made sixteen well-received broadcasts. Evangelists (people who try to convert others to Christianity) also used the airwaves to address their followers and attract more converts.

Regulations

The phenomenal growth of the radio industry led to the founding of the Federal Radio Commission in 1927. The purpose of the agency was to develop and enforce broadcasting rules and regulations. By the end of the decade, one-third of the total U.S. population—about twelve million homes—reportedly listened to the radio on a regular basis. The Federal Radio Commission changed its name to the Federal Communications Commission in 1934. The new name reflected the fact that regulations now extended to the telephone industry.

Radio continued through the 1930s and 1940s primarily as an entertainment vehicle. But in 1948, network television came on strong, and many radio stars moved over to the new visual medium. Radio survived, however. By 1949, there were 80 million radios in the United States. In 1965 there were 228 million. The small, handy, inexpensive transistor radio was now popular.

In the 1960s, music began to take on a more prominent role on the radio. The most successful format was Top 40; stations played only the most popular records listed by Billboard magazine. Disc jockeys, or DJs, kept programs moving, identifying the station, letting listeners know what songs were playing, and making sure commercials ran so that radio stations maintained their revenues. Stations began catering to specific tastes, such as rock and roll , and different demographics, such as African Americans.

By the 1980s, 99 percent of American households owned radios, and each household had an average of 5.5 radios (not including car radios). Most programming was produced locally, as opposed to the more national feel of television. FM programming rose in the 1980s, due largely to its superior sound quality. Music stayed primarily on FM, while AM became known more for its news, sports, and call-in programs. This trend continued into the twenty-first century.

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Radio

RADIO

The most important new mass medium of the Depression era had evolved dramatically in earlier decades. The development of telegraphy in the nineteenth century, along with investigations into electromagnetism, gave rise in the late 1800s to the genesis of wireless communications. At the turn of the century Guglielmo Marconi invented the first devices that transmitted bits of Morse Code via electromagnetic waves, using an oscillating electrical circuit. Wireless telegraphy soon bridged the Atlantic and announced Robert E. Peary's arrival at the North Pole, and it would dominate the wireless scene into the 1910s. Meanwhile, though, American scientists led by Lee De Forest developed vacuum tubes that could receive and reproduce the human voice and other transmitted sound. The Radio Corporation of America (RCA) was formed in 1919, after the military ceased its wartime control of wireless communications. RCA and other companies produced the first crystal radio kits, receivers for individual listeners that required the use of earphones.

The first radio station had been established in San Jose, California, in 1909, but modern radio broadcasting began with the formation in 1920 of KDKA in Pittsburgh. Victrola records were played into a "wireless telephone" or pick-up microphone and broadcast (a term invented at KDKA) over a three-state area; a music store soon allowed unlimited playing of its disks in return for on-air promotions. On election night 1920, amplified kits were arrayed in movie houses and other halls where Pittsburghers received returns. By 1922 local stations across the United States were broadcasting concerts, sermons, and political speeches. Vaudeville and musical performers, such as Ed Wynn and Paul Whiteman, soon appeared regularly on radio, and such broadcasters as Milton Cross, Walter Damrosch, and "Major" Edward Bowes also were heard. All remained popular through the Depression era. Bandleaders placed "wires" or radio transmitters into ballrooms and transmitted their music beyond the immediate dance floor. By 1928 shortwave transatlantic broadcasts were possible. Labor unions, political parties, and municipalities began their own stations in this early era of democratic experimentation.

Overlapping frequencies and distorted signals increased the demand for regulation or standardization in radio. While Britain's government nationalized the airwaves in 1922, creating the British Broadcasting Company (BBC), David Sarnoff of RCA and others in the United States pushed for a commercially-sponsored system of radio networks that would dominate programming and the widestband (AM, or "amplitude modulation") signals. In 1926 RCA's National Broadcasting Company (NBC) became the first radio network. The next year NBC transmitted the Rose Bowl game coast-to-coast. That same year the Radio Act became law, protecting the interests of networks and relegating nonaffiliated local stations to narrower, less-powerful frequencies. NBC actually ran two networks, the Blue and the Red, derived from existing station alliances; these were joined in 1929 by the Columbia Broadcasting System (CBS), founded by William Paley, and in 1934 by the Mutual Broadcasting System. All of them featured predominantly musical programs, often sponsored and funded by a commercial advertiser. Product advertising thus took a quantum leap forward with the arrival of radio's electronic mass-marketing. On the eve of the Depression radio receivers were attached to loudspeakers that allowed families and other groups to listen together, and the problems of air-wave static and tinny-sounding pickup microphones were increasingly overcome by technological improvements. Just as Wall Street crashed, radio was becoming a major communications phenomenon.

By the end of the 1920s domestic and small-town melodramas (the first "soap operas," presented by Palmolive and other sponsors), sermons, band and symphony broadcasts, primitive infomercials featuring "blindfold tests," quiz shows, speeches by presidents and other notables, and children's series derived from comic strips were everyday fare for millions. Educators and others condemned the lowbrow content of radio series—"This child of mine is moronic," Lee De Forest lamented—and new legislation sought to regulate the content of children's programming. By the fall of 1929, though, the antics of Amos 'n' Andy, two shiftless and comical Negro caricatures portrayed by the white actors Charles Correll and Freeman Gosden, had conquered the national audience. Amos 'n' Andy appeared for a quarter hour at 7:00 p.m. every Monday through Saturday and created an unprecedented following, even among millions of African-American listeners. Supporting characters, such as the Kingfish and Senator Claghorn, helped construct a comical vision of American race relations that reinforced the passivity of most Americans regarding such issues as civil rights and lynching. Vaudeville-style ethnic programming such as The Rise of the Goldbergs soon followed, and a culture of celebrity grew up around such crooning variety-show hosts as Rudy Vallée and Bing Crosby. Vallée is credited with popularizing the variety show format, which became standard. Vaudeville comics such as Jack Benny, George Burns and Gracie Allen, Fred Allen, and Bob Hope also became radio stars, and like Vallée and Crosby they also crossed over into successful motion picture careers.

Journalism was a decidedly minor aspect of the networks' programming, despite the efforts of pioneering commentators such as H. V. Kaltenborn and reporters such as Edward R. Murrow and Robert Trout, and it was often obscured by the trivial but wildly popular "reporting" of gossip-dispensers such as Walter Winchell and Louella Parsons. Into the early 1930s, in short, network radio solidified its presence as mass entertainment in a box, bringing ephemeral diversions and capitalism's thirtysecond fables into almost every living room and eatery.

Radio nevertheless still showed some diversity. The Depression made it far more difficult for grass-roots local stations to survive, but some were able to continue to offer alternatives to the networks' mass-oriented fare. Union dues and listeners' subscriptions kept dozens of low-wattage stations on the air. In New York City, the Socialist Party's WEVD (named after the party's founder, Eugene V. Debs) dispensed news, discussions, and jazz by both black and white musicians. Regional arrangements targeted subgroups of the national audience as well, such as the syndicated networks that broadcast WMC-Nashville's Grand Ole Opry across the South and WLS-Chicago's Barn Dance in the Midwest. Even these regional trends, though, increasingly made radio a homogeneous, standardized corporate product that, like movies, had the effect of "massifying" American culture to an unprecedented degree.

With the deepening of the Great Depression, radio brought basic political discourse into almost every home for the first time. In 1921, as secretary of commerce, Herbert Hoover had been the first American public official to give a radio address. A decade later, now a beleaguered president, Hoover was a regular but notably ineffective presence on the airwaves. He fell prey to the criticisms of such network commentators as Father Charles E. Coughlin of Royal Oak, Michigan, whose NBC-broadcast Sunday sermons became increasingly political and polemical in nature. (High listener ratings—first tabulated in the early 1930s—ensured that Coughlin kept his radio platform for a long time.) In 1932, broadcast political conventions and campaign oratory helped to ensure Hoover's defeat and a landslide victory for Franklin D. Roosevelt.

Roosevelt pioneered the intimate presidential radio address, intended solely for the mass audience in their homes. His first "fireside chat" took place just days after he took office, and he made three more such broadcasts in 1933. In the first two years of his term he spoke on national radio forty times, in public and in "fireside" settings, and his audiences were almost always large. This trend continued into his second term; a fireside chat in March 1937 was heard by a third of the entire radio audience. The intense ideological struggles between Roosevelt's New Dealers and opponents on the political right (such as Hoover and Alfred E. Smith) and on the left (such as Norman Thomas, Huey Long, and Father Coughlin) were serialized in an extended debate over the radio waves, democratizing the great political discourse of the day to an unprecedented degree. However, radio's journalistic coverage of actual grassroots suffering during the Depression was minimal. Meanwhile, radio became increasingly regulated during the New Deal. In 1934 the new Federal Communications Commission (FCC) began more intense scrutiny of the operations of networks and small stations.

Network radio's artistic standards improved markedly in the late 1930s. Executives partially took the critics' scorn to heart and sought out more substantial talent, especially in the field of writing. In 1936 CBS's Columbia Workshop began presenting experimental original work by Irwin Shaw, Archibald MacLeish, James Thurber, Steven Vincent Benét, and others, as well as Aldous Huxley narrating an adaptation of his novel Brave New World. Bernard Herrmann's musical scores enhanced the program's quality as well. Similar programs such as The Theater Guild on the Air (for which Arthur Miller wrote) signaled the increased translation of good drama from stage to sound studio, while the Lux Radio Theater adapted high-quality motion pictures to radio, featuring the original screen stars. Norman Corwin began a distinguished career as a creator of thoughtful dramatic programs, while Arch Oboler churned out hundreds of expertly-crafted mysteries, adventure stories, and kitchen-table dramas.

The most notable risk was taken in 1937 by CBS, when Orson Welles, the 22-year-old sensation of the avant-garde theater (and already a veteran radio performer), was given the Mercury Theater on the Air. Welles's versions of classic and popular literature caused little controversy until his October 30, 1938, broadcast of H. G. Wells's War of the Worlds. By then, Americans had grown familiar with broadcasts of the tirades of Adolf Hitler and Benito Mussolini, and network news departments had intensified their coverage of such world issues as Europe's move toward war. Welles's pseudojournalistic approach to the martian invasion, featuring a simulated news broadcast that evoked the memorable coverage of the 1937 explosion of the dirigible Hindenburg (which, like the "invasion," took place in New Jersey), fooled and terrified thousands of listeners, who were convinced that the war of the worlds had actually begun. The FCC warned the networks not to allow such provocative and clever deceptions in the future. The specter of censorship had also been raised in 1937, when Mae West performed a risqué comedy sketch by Arch Oboler, The Garden of Eden, and the FCC received hundreds of complaints. The Welles controversy showed, above all, that radio could be a powerful expression and reflection of a troubled nation's mood.

By the late 1930s radio's prominence as a social force was being acknowledged by cultural commentators and scholars. Princeton University began an Office of Radio Research to explore the content of radio programming and its impact on the attitudes and lives of listeners. Exiled Central European scholars such as Paul Lazarsfeld and Theodor Adorno provided intellectual ballast to Princeton's investigations. Adorno in particular published studies that revealed, through his Marxist critical perspective, patterns of manipulation and degradation in the consciousness of the mass of American listeners. Such perspectives were hotly debated, but they also indicated the growth of a body of critical analysis in mass communications that increasingly shaped the response of educated Americans to radio and other electronic media. It was one more indication of the wide and diverse impact of radio on American culture during the 1930s.

As the 1930s closed, radio continued to evolve. FCC pressure on the networks to surrender their monopolies increased; antitrust legislation would eventually be brought against NBC and force it to divest its Blue network. Despite the dangers of monopolization, however, unaffiliated local radio stations grew in number. Increasingly they pioneered the use of disk jockeys, listener research, and package deals with record companies, while some of them also became guardians of regional and special musical styles, such as country-western and big-band jazz. African-American musicians faced much discrimination in radio, but their invisibility in that medium allowed more bands and soloists to appear than in films or on vaudeville touring circuits. Also before 1940, FM (frequency modulation) radio was introduced, promising more true-to-life transmissions in the near future. Television's stalled development before 1940 also ensured the primacy of radio in America's living rooms. In short, despite the difficulties caused by the Depression and the dominance of the networks—and sometimes because of it—radio made stunning advances and caused decisive transformations in American communications and culture.

See Also:AMOS 'N' ANDY; COMMUNICATIONS ACT OF 1934; COMMUNICATIONS AND THE PRESS; COUGHLIN, CHARLES; FEDERAL COMMUNICATIONS COMMISSION (FCC); FIRESIDE CHATS; WELLES, ORSON.

BIBLIOGRAPHY

Barnouw, Eric. A Tower in Babel: A History of Broadcasting in the United States to 1933. 1966.

Barnouw, Eric. The Golden Web: A History of Broadcasting in the United States, 1933–1953. 1968.

Douglas, Susan J. Inventing American Broadcasting, 1899–1922. 1987.

Hilliard, Robert L., and Michael C. Keith. The Broadcast Century: A Biography of American Broadcasting, 3rd edition. 2001.

MacDonald, J. Fred. Don't Touch That Dial! Radio Programming in American Life, 1920 to 1960. 1979.

Smulyan, Susan. Selling Radio: The Commercialization of American Broadcasting, 1920–1934. 1994.

Sterling, Christopher H., and John Michael Kittros. Stay Tuned: A History of American Broadcasting, 3rd edition. 2001.

Summers, Harrison B., ed. A Thirty-Year History of Programs Carried on National Radio Networks in the United States, 1926–1956. 1971.

Burton W. Peretti

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Radio

Radio

In September of 1895, Guglielmo Marconi, a young Italian inventor, pioneered wireless telegraphy when he transmitted a message to his brother, who was out of sight beyond a hill. By 1906, U.S. inventor Lee De Forest had greatly increased the potential of Marconi's work by developing a three-electrode vacuum-tube amplifier that made modern radio broadcasts possible. From these relatively humble beginnings radio quickly evolved to become the basis of an electronic media revolution that would shape the face of American popular culture during the middle years of the twentieth century. From the early 1920s to the mid-1950s radio both recorded and influenced popular culture in a way that no other media had ever done, forever changing the way information and entertainment would be disseminated and paving the way for television.

The first modern radio station came into being in 1920, when Westinghouse engineer Frank Conrad set up KDKA in East Pittsburgh, Pennsylvania, and began sending out programs "over the ether," in the parlance of the day. On November 2 of that year, KDKA broadcast the results of the Harding-Cox presidential election. However, at that time only about 5,000 Americans had radio receivers, so the broadcast went largely unnoticed. As Susan Smulyan writes in Selling Radio, the problem was that "when the first radio station began in 1920, no one knew how to make money from broadcasting." Nevertheless, a number of different groups soon realized that radio could be a powerful and important medium, which resulted in a battle for control of the airwaves.

One faction, spearheaded primarily by educators, believed that radio could be a tool for enriching people's lives. They wanted a government-funded national radio program that would be largely informational and educational. These groups would have to wait nearly fifty years to get their wish; on November 7, 1967, President Lyndon B. Johnson would sign the Public Broadcasting Act into law, resulting in the creation of the noncommercial National Public Radio and the Public Broadcasting (television) networks. But in 1920 the question for broadcasters was, "Who would pay for radio?" The general public was not yet ready to pay for its information and entertainment directly (that would come in the 1970s, with the growth of cable television beyond its humble beginnings as a source for programming in areas beyond the reach of airborne signals). In 1922 New York radio station WEAF—which would later become WNBC—solved the funding dilemma when it aired the first paid radio commercials. Although advertisers were initially unconvinced as to radio's ability to sell products, they eventually realized that it was an incredibly effective way to reach people in their homes. Accordingly, WEAF's commercialization set into motion the private control of U.S. public airwaves. In a now-famous quote, radio pioneer De Forest responded to radio's commercialization by asking, "What have you done with my child? You have sent him out on the street in rags of ragtime to collect money from all and sundry. You have made of him a laughingstock of intelligence, surely a stench in the nostrils of the gods of the ionosphere."

The concept of "selling time" for advertisements had immense ramifications for American popular culture. Since the inception of mass media advertising, the public's conception of life in the United States has become defined not by what people do, but by the products they consume; success or failure in the U.S. is largely defined by material possessions instead of by accomplishments. As Smulyan writes, "broadcasting's programs and structures," which paved the way for later media advertising like television commercials and website banners, were first "developed in radio." However, radio's contribution to popular culture is not exclusively confined to its role in the birth of modern advertising. Just as important are the medium's contributions to the ways in which people are informed and entertained.

Prior to the onset of the Depression, radio had already established its core of music, news, and entertainment programming. Of the three, music and news programming were the most predominant because they were the cheapest to produce; entertainment programming would not enter its golden age until the early 1930s. There were two ways of presenting music on radio: either by playing records or broadcasting musicians as they played live in a studio, concert hall, or hotel ballroom. The widespread integration of musical numbers into more complex variety shows was still a number years off. In addition to musical programming, news broadcasts and issue-based discussion shows also flourished in the 1920s. Never before had the dissemination of news been so immediate. Sports events like the World Series and news events like the infamous Scopes trial, which Chicago station WGN broadcast live, united Americans around their radios. From its earliest days, radio began the move towards instantaneous news.

Radio networks also began appearing in the late 1920s: NBC was established in 1926, and CBS in 1927. Perhaps the most important effect these networks had on radio was their contribution to the establishment of a more national medium. The respective networks began buying up local stations, which became known as "affiliates." Locally produced shows gave way to uniform national shows that the networks broadcast over their affiliates. Concurrently, radio was becoming an item commonly found in every home. As noted by Fred MacDonald in Don't Touch That Dial, by the early 1930s approximately 90 percent of Americans had at least one radio in their homes. As a result, American regionalism began to disappear at an accelerated rate as Californians began to hear the same shows as people in Alabama and New Jersey. What in the late 1990s has come to be known as the "homogenization of American culture" can be traced back to the rise of the early radio networks.

Despite the success of radio in the 1920s, something was still missing. Although there were a few popular programs, radio shows had yet to fully come into their own; however, the Great Depression ushered in their "golden age." By the early 1930s, listeners had grown bored with mostly music, news, and talk, and many of them craved escape from the hard reality of their difficult financial circumstances. Radio responded by expanding its programming diversity and broadcasting shows in many genres, including Westerns, detective shows, dramas, soap operas, comedies, romances, and variety shows. Americans danced to the latest rhythms as played by bandleaders who broadcast live from hotel ballrooms, or gathered around their radio sets on Sunday morning to hear prominent preachers and choirs, precursors to the radio and television evangelists of a later era. Many radio shows of the period were serialized so fans could follow the ongoing weekly adventures of their favorite characters. The serialization of radio shows created a continuity in American entertainment that was unique to the medium at that time. The Lone Ranger, for example, was on the air for twenty-two years. Likewise, The Jack Benny Program enjoyed a twenty-six-year run. Perhaps MacDonald best sums up radio's importance during the Depression when he writes, "for audiences trapped by the economic depression and social uncertainty of the 1930s, radio became the great wellspring from which came escape, diversion, knowledge, and inspiration." As programmers realized that national shows needed national celebrities in order to achieve immediate success, they came to rely heavily on the many popular performers who had been displaced by the rise of electronic media—making radio stars out of ex-vaudevillians like the Marx Brothers, Burns and Allen, Jack Benny, and Fred Allen.

Conversely, in the early 1930s, entertainment's brightest lights—Hollywood movie stars—were reluctant to appear on radio. Most studios, and many stars, believed that appearing on radio would somehow lessen a star's cinematic appeal. Radio loved the movies, on the other hand: most stations ran movie reviews, and syndicated gossip columnists such as Louella Parsons and Walter Winchell often focused on Hollywood figures. Hollywood studios eventually came to the realization that increased exposure for their stars would most likely result in increased revenues for their films. By the early 1940s Hollywood actors, including Humphrey Bogart, Katharine Hepburn, Jimmy Stewart, James Cagney, and Clark Gable, routinely participated in radio reenactments of their films; at the same time a number of actors who got their start in radio, such as Don Ameche, Richard Widmark, Agnes Moorehead, and Art Carney, were beginning to appear in films. As the lines between the two media slowly blurred, America became more and more infatuated with its stars. As a result of the unprecedented media exposure stars received when they began to appear both on radio and in film, the cultural iconolatry of entertainers, which began in earnest with the silent movie stars of the late 1910s and early 1920s, reached new heights in the 1930s and 1940s.

Perhaps the most vivid example of the cultural influence radio had in its heyday is Orson Welles' October 30, 1938, broadcast of an adaptation of H. G. Wells' The War of the Worlds, which presented itself as a would-be Martian invasion broadcast in real time. Welles and the other actors meant the broadcast to be dramatic fiction, but millions took it seriously. Although the show did run an opening explanation, many who tuned in late were greeted by an announcer saying, "Ladies and gentlemen, we interrupt our program of dance music to bring you a special bulletin from the Intercontinental Radio News." Listeners mistakenly believed that Martians were invading the United States and that radio was covering it live. All over the country hysteria prevailed for several hours, and the power of radio to influence the American public was confirmed.

Just as radio entertainment became more diversified during the 1930s, so too did the ways in which news was presented. Whereas in the 1920s and early 1930s news had most often been simply read, a new type of reporter was coming into being in the mid-1930s: the broadcast journalist. Reporters began live coverage of developing stories and often offered on-air appraisals of news stories as they happened. Americans who had previously only heard reporters reading recaps of speeches, conferences, conventions, and military clashes began to hear them live. These live broadcasts of social and political events played a large role in America's national attitude of unity as it entered World War II. The public had been largely uninformed when America entered World War I, but because of radio and its broadcast journalists the American public was keenly aware of the cumulative series of events that had occurred prior to its entering World War II.

As radio grew, politicians realized its importance as a means through which to disseminate their ideology. In an extreme example, European leaders such as Mussolini and Hitler routinely broadcast their fervent speeches live. Although their message was often one of hatred and intolerance, both leaders—but especially Hitler—were brilliant and impassioned speakers who understood just how effective a propaganda tool radio could be. Perhaps the most fervent ideologue on U.S. radio in the late 1930s was Father Charles Coughlin, the "radio priest" of Royal Oak, Michigan, who commanded an audience of millions with tirades that became increasingly anti-Semitic and pro-Franco. On the home front, perhaps no U.S. leader used radio as effectively as President Franklin Delano Roosevelt. Beginning in 1933 and lasting until his death in 1945, Roosevelt took his message directly to the people in a series of live radio speeches. Roosevelt called some of these speeches "fireside chats," which were constructed to seem like personal conversations with the public. Opening each chat with the phrase, "My dear friends," Roosevelt carefully explained his policies and programs and used the intimate format to gain popular support from the American people. In addition, Rooseveltian sound bites such as "the only thing we have to fear is fear itself" (from his first inauguration) and "a date which will live infamy" (from his speech to Congress after Pearl Harbor) were immediately and permanently thrust into the nation'a popular culture, in part because they were broadcast live to an audience of millions.

Throughout U.S. involvement in World War II, radio played a crucial role in the public's perception of the war. Although not televised as the Vietnam War would later be, radio brought World War II into every American living room. From Britain and France's declaring war on Germany in 1939, to Roosevelt's "day of infamy" speech after the attack on Pearl Harbor, to the surrender ceremonies aboard the U.S.S. Missouri on September 2, 1945, Americans heard the war's major events as they happened. Perhaps the most memorable broadcasts of the war were Edward R. Murrow's reports during the London blitz of 1940, which helped solidify U.S. public opinion on behalf of the Allies. As the war proceeded, and despite strict censorship restrictions, other broadcast journalists reported from military hot spots and the government used radio to communicate with the nation. All through the war Americans turned to their radios for the latest news from the fronts. In addition to the first-hand accounts of those returning from overseas and newsreels, America's memories of World War II have been shaped largely by the immediacy offered by radio.

Although radio continued to enjoy tremendous popularity in the early 1950s, it was never quite the same after World War II. The war had given radio a uniformity of purpose and focus. With the war over, radio was forced to scramble to institute peacetime programming that could match the heady days of broadcasting during the war years. As traditional formats began to lose popularity, it became clear that new formats and ideas were needed; but radio was slow to change. Experimentation was limited by the cold war atmosphere of fear created by the anti-Communist movement of the late 1940s and early 1950s. Producers were afraid that anything different from the norm might be construed as subversive. Concurrently, television was beginning to gain a firm hold in American homes. Many of the shows that had long been broadcast on the radio made the transition to television. By 1960 the golden age of radio was over.

Radio has never fully regained the popularity it enjoyed during its forty-year heyday from 1920 to 1960. The rise of FM radio stations in the 1960s propelled rock 'n' roll to a position of cultural influence unequaled by any other musical genre. FM stations sounded better than AM stations, and came in stereo. The disc jockeys who played records took advantage of their new-found freedom to experiment with the FM dial as "free form" radio. Whereas radio news had chronicled the cultural events of the 1930s, 1940s, and 1950s, rock 'n' roll became the sound track for the cultural revolution ushered in by the Boomer generation in the 1960s and early 1970s. Before World War II, most radio programs, dramas, comedies, musical shows, or quiz shows, were fifteen-minute or half-hour programs; after the war, stations tended to devote round-the-clock programming to specific musical formats, such as rock 'n' roll, Top-40, classical, rhythm & blues, or jazz, for example. In the 1990s, talk radio enjoyed a resurgence, especially on the AM dial, with figures as diverse as Rush Limbaugh, Dr. Laura Schlessinger, and Howard Stern enjoying a cultural influence perhaps never equaled by their radio predecessors—to say nothing of the frank sex therapy dispensed by Dr. Ruth Westheimer and Dr. Judy Kurlansky.

During the height of radio's popularity, as Charles Siepmann writes, "The average man or woman spends more leisure hours in listening to the radio than in anything else—expect sleeping.… For radio—cheap, accessible, and generous in its provision for popular tastes—has come to be the poor man's library, his 'legitimate' theater, his vaudeville, his newspaper, his club. Never before has he met so many famous and interesting people, and never have these people been at once so friendly and so attentive to his wishes." On the eve of the year 2000, American audiences had immediate access to more news and entertainment options than any population in the history of the world; radio was the seed from which the structure of contemporary current mass media grew. But America's plethora of options reflects its culture: fractious, scattered, and able to agree on little. Conversely, for a brief forty years in the mid-twentieth century, radio contributed to the creation of at least the semblance of a united country and inspired the national imagination in a way no medium has done before or since.

—Robert C. Sickels

Further Reading:

Bray, John. The Communications Miracle: The Telecommunication Pioneers from Morse to the Information Superhighway. New York, Plenum Press, 1995.

Hilmes, Michele. Radio Voices: American Broadcasting, 1922-1952. Minneapolis, University of Minnesota, 1997.

Ladd, Jim. Radio Waves: Life and Revolution on the FM Dial. New York, St. Martin's Press, 1991.

MacDonald, Fred J. Don't Touch That Dial: Radio Programming in American Life, 1920-1960. Chicago, Nelson-Hall, 1979.

Maltin, Leonard. The Great American Broadcast: A Celebration of Radio's Golden Age. New York, Dutton, 1997.

Nachman, Gerald. Raised on Radio. New York, Pantheon Books, 1998.

Ryan, Thomas. American Hit Radio: A History of Popular Singles from 1955 to the Present. Rocklin, California, Prima Publishing, 1996.

Smulyan, Susan. Selling Radio: The Commercialization of American Broadcasting, 1920-1934. Washington, D.C., Smithsonian Institution Press, 1994.

Urban, George E. Radio Free Europe and the Pursuit of Democracy: My War within the Cold War. New Haven, Connecticut, Yale University Press, 1997.

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Radio

Radio

Radio is the technology and practice that enables the transmission and reception of information carried by long-wave electromagnetic radiation . Radio makes it possible to establish wireless two-way communication between individual pairs of transmitter and receiver, and it is used for one-way broadcasts to many receivers. Radio signals can carry speech , music, telemetry , or digitally-encoded entertainment. Radio is used by the general public, within legal guidelines, or it it is used by private business or governmental agencies. Cordless telephones are possible because they use low-power radio transmitters to connect without wires. Cellular telephones use a network of computer-controlled low power radio transmitters to enable users to place telephone calls away from phone lines.

The history of radio

In the nineteenth century, in Scotland, James Clerk Maxwell described the theoretical basis for radio transmissions with a set of four equations known ever since as Maxwell's Field Equations. Maxwell was the first scientist to use mechanical analogies and powerful mathematical modeling to create a successful description of the physical basis of the electromagnetic spectrum . His analysis provided the first insight into the phenomena that would eventually become radio. He deduced correctly that the changing magnetic field created by accelerating charge would generate a corresponding changing electric field. The resulting changing electric field would, he predicted, regenerate a changing magnetic field in turn, and so on. Maxwell showed that these interdependent changing electric and magnetic fields would together be a part of a self-sufficient phenomenon required to travel at the speed of light .

Not long after Maxwell's remarkable revelation about electromagnetic radiation, Heinrich Hertz demonstrated the existence of radio waves by transmitting and receiving a microwave radio signal over a considerable distance. Hertz's apparatus was crude by modern standards but it was important because it provided experimental evidence in support of Maxwell's theory.

Guglielmo Marconi was awarded the Nobel Prize in physics in 1909 to commemorate his development of wireless telegraphy after he was able to send a long-wave radio signal across the Atlantic Ocean.

The first radio transmitters to send messages, Marconi's equipment included, used high-voltage spark discharges to produce the charge acceleration needed to generate powerful radio signals. Spark transmitters could not carry speech or music information. They could only send coded messages by turning the signal on and off using a telegraphy code similar to the landline Morse code.

Spark transmitters were limited to the generation of radio signals with very-long wavelengths, much longer than those used for the present AM-broadcast band in the United States. The signals produced by a spark transmitter were very broad with each signal spread across a large share of the usable radio spectrum . Only a few radio stations could operate at the same time without interfering with each other. Mechanical generators operating at a higher frequency than those used to produce electrical power were used in an attempt to improve on the signals developed by spark transmitters.

A technological innovation enabling the generation of cleaner, narrower signals was needed. Electron tubes provided that breakthrough, making it possible to generate stable radio frequency signals that could carry speech and music. Broadcast radio quickly became established as source of news and entertainment.

Continual improvements to radio transmitting and receiving equipment opened up the use of successively higher and higher radio frequencies. Short waves, as signals with wavelengths less than 200m are often called, were found to be able to reach distant continents. International broadcasting on shortwave frequencies followed, allowing listeners to hear programming from around the world.

The newer frequency-modulation system, FM, was inaugurated in the late 1930s and for more than 25 years struggled for acceptance until it eventually became the most important mode of domestic broadcast radio. FM offers many technical advantages over AM, including an almost complete immunity to the lightning-caused static that plagues AM broadcasts. The FM system improved the sound quality of broadcasts tremendously, far exceeding the fidelity of the AM radio stations of the time. The FM system was the creation of E. H. Armstrong, perhaps the most prolific inventor of all those who made radio possible.

In the late 1950s, stereo capabilities were added to FM broadcasts along with the ability to transmit additional programs on each station that could not be heard without a special receiver. A very high percentage of FM broadcast stations today carry these hidden programs that serve special audiences or markets. This extra program capability, called SCA for Subsidiary Communications Authorization, can be used for stock market data, pager services, or background music for stores and restaurants.


Radio and the electromagnetic spectrum

Radio utilizes a small part of the electromagnetic spectrum, the set of related wave-based phenomena that includes radio along with infrared light, visible light, ultraviolet light, x rays , and gamma rays. Picture the electromagneticspectrum as a piano keyboard: radio will be located where the piano keys produce the low frequency musical notes. Radio waves have lengths from many miles down to a fraction of a foot.

Radio waves travel at the velocity of electromagnetic radiation. A radio signal moves fast enough to complete a trip around the earth in about 1/7 second.


How radio signals are created

Jiggle a collection of electrons up and down one million times a second and a 1-MegaHertz radio signal will be created. Change the vibration frequency and the frequency of the radio signal will change.

Radio transmitters are alternating voltage generators. The constantly changing voltage from the transmitter creates a changing electric field within the antenna . This alternating field pushes and pulls on the conduction electrons in the wire that are free to move. The resulting charge acceleration produces the radio signal that moves away from the antenna. The radio signal causes smaller sympathetic radio frequency currents in any distant electrical conductor that can act as a receiving antenna.


Modulation

A radio signal by itself is like a mail truck without letters. A radio signal alone, without superimposed information, is called a carrier wave. An unmodulated radio signal conveys only the information that there was once a source for the signal picked up by the receiver. Adding information to a carrier signal is a process called modulation. To modulate a radio carrier means that it is changed in some way to correspond to the speech, music, or data it is to carry.

The simplest modulation method is also the first used to transmit messages. The signal is turned on and off to transmit the characters of an agreed code. Text messages can be carried by the signal modulated in this way. Unique patterns stand for letters of the alphabet, numerals, and punctuation marks.

The least complicated modulation method capable of transmitting speech or music varies the carrier signal's instantaneous power. The result is called amplitude modulation, or AM. Another common system varies the signal's instantaneous frequency at an informational rate . The result is frequency modulation, FM.

If radio is to transmit speech and music, information must be carried that mimics the pattern of changing air pressure the ear would experience hearing the original sound. To transmit sounds these air-pressure changes are converted into electrical signals, amplified electronically, then used to modulate the carrier.

Amplitude modulation was the first process to have the capability of transmitting speech and varied the radio signal's instantaneous power at a rate that matched the original sound vibrations in the air. A better modulation technology followed that varied the instantaneous frequency of the radio signal but not the amplitude. Frequency modulation, or FM, has advantages compared to AM but both AM and FM are still in use.

Sound can be converted to digital data, transmitted, then used to reconstruct the original waveform in the receiver. It seems likely that a form of digital modulation will eventually supplant both FM and AM.


Demodulation

Radio receivers recover modulation information in a process called demodulation or detection. The radio carrier is discarded after it is no longer needed. The radio carrier's cargo of information is converted to sound using a loudspeaker or headphones or processed as data.


Wavelengths, frequencies, and antennas

Each radio signal has a characteristic wavelength just as is the case for a sound wave. The higher the frequency of the signal, the shorter will be the wavelength. Antennas for low-frequency radio signals are long. Antennas for higher frequencies are shorter, to match the length of the waves they will send or receive.

It is a characteristic of all waves, not just radio signals, that there is greater interaction between waves and objects when the length of the wave is comparable to the object's size. Just as only selected sound wavelengths fit easily into the air column inside a bugle, only chosen frequencies will be accepted by a given antenna length. Antennas, particularly transmitting antennas, function poorly unless they have a size that matches the wavelength of the signal presented to them. The radio signal must be able to fit on the antenna as a standing wave. This condition of compatibility is called resonance . If a transmitter is to be able to "feed" energy into an antenna, the antenna must be resonant or it will not "take power" from the transmitter. A receiver antenna is less critical, since inefficiency can be compensated by signal amplification in the receiver, but there is improvement in reception when receiving antennas are tuned to resonance.

If an antenna's physical length is inappropriate, capacitors or inductors may be used to make it appear electrically shorter or longer to achieve resonance.

Near 100 MHz, near the center of the FM broadcast band in most of the world, signals have a wavelength of approximately three meters. At 1 MHz, near the center of the U.S. AM broadcast band, the signal's wavelength is 327 yds (300 m), about three times the length of a football field. One wavelength is about 1 ft (0.3 m) at the ultra-high frequency used by cellular telephones.


Radio signals and energy

Energy is required to create a radio signal. Radio signals use the energy from the transmitter that accelerates electric charge in the transmitting antenna. A radio signal carries this energy from the transmitting antenna

to the receiving antenna. Only a small fraction of the transmitter's power is normally intercepted by any one receiving antenna, but even a vanishingly-small received signal can be amplified electronically millions of times as required.


Radio signal propagation

Radio signals with very short wavelengths generally follow straight line paths much as do beams of light, traveling from transmitter to receiver as a direct wave. Radio signals with very long wavelengths follow the curvature of the earth, staying close to the surface as signals called ground waves.

Radio signals with intermediate wavelengths often reflect from layers of electrically-charged particles high above the earth's surface. These signals are known as skywaves. The layers of electrically-charged particles found between 25-200 mi (40-322 km) above the earth are collectively known as the ionosphere. The ionosphere is renewed each day when the sun's radiation ionizes atoms in the rarefied air at this height. At higher altitudes the distance between ions causes the ionization to persist even after the sun sets.

A good way to become familiar with radio propagation is to listen for distant AM-broadcast radio at various times of the day. A car radio works well for this experiment because they often have better sensitivity and selectivity than simpler personal radios.

During the daylight hours, on the standard-broadcast band, only local stations will normally be heard. It is unlikely that you will hear stations from more than 150 mi (241 km). As the sun sets you will begin to hear signals from greater distances.

AM-broadcast reception is generally limited to ground-wave radio signals when the sun is high in the sky. There is a very dense layer of the ionosphere at a height of approximately 25 mi (40 km) that is continually created when the sun is high in the sky. This D layer, as it is called, absorbs medium wavelength radio signals so that skywave signals cannot reflect back to earth. The D layer dissipates quickly as the sun sets because the sun's rays are needed to refresh the ionization of this daytime-only feature of the ionosphere. After dark, when the D layer has disappeared, you will hear strong signals from far away cities.

After the D layer has disappeared, skywave signals reflect from a much higher layer of the ionosphere called the F layer. The F layer acts as a radio mirror, bouncing skywaves back to earth far from their source. The F layer degrades in darkness as does the D layer, but since the ions are separated more widely at higher altitude, the F layer functions as a significant radio mirror until dawn. Toward morning stations at intermediate distances fade, leaving only skywave signals that reflect from the thinning ionosphere at a very shallow angle.

Signal absorption by the D layer is less at shorter wavelengths. Stations using higher frequencies can use skywave in the daytime. High frequencies pass through the D layer. Skywave radio circuits are usually best in the daytime for higher frequencies, just at the time that the standard-broadcast band is limited to groundwave propagation.

Forecasting long distance radio signal propagation conditions depends upon predicting conditions on the sun. It is the changing radiation from the sun that affects long distance radio circuits when the ionosphere changes as the earth rotates. On the sunlit side of the earth the ionosphere is most strongly ionized. On the night side of the earth the radio ionosphere begins to dissipate at sunset until it is almost insignificant as a radio mirror in the early morning hours. When the ionosphere is at its best as a reflector it can support communication between any locations on the earth.

When the ionosphere is more densely ionized it will reflect radio signals with a shorter wavelength than when the ionization is weaker. At any one time, between any two distant locations on the earth, there is a limiting upper frequency that can be used for radio communication. Signals higher in frequency than this maximum-usable frequency, F layer called the MUF, pass through the ionosphere without returning to earth. Slightly lower than the MUF, signals are reflected with remarkable efficiency. A radio signal using less power than a flashlight can be heard on the opposite side of the earth just below the MUF. The MUF tends to be highest when the sun is above the midpoint between two sites in radio communication.

The 11-year solar sunspot cycle has a profound effect on radio propagation. When the average number of sunspots is large, the sun is more effective in building the radio ionosphere. When the sun's surface is quiet the maximum-usable frequency is usually very low, peaking at less than half the MUF expected when the sun surface is covered with sunspots.

From time to time, the sun bombards the earth with charged particles that disrupt radio transmissions. When solar flares are aimed toward the earth, the earth's magnetic field is disturbed in a way that can cause an almost complete loss of skywave radio propagation. Microwave radio signals are not significantly disturbed by the magnetic storms since microwaves do not depend upon ionospheric reflection.

FM-broadcast signals are seldom heard reliably further than the distance to the horizon. This is because the frequencies assigned to these services were deliberately chosen to be too high to expect the ionosphere to reflect them back to earth. FM signals are received as direct waves, not skywaves. The limited range of FM stations is an advantage because frequency assignments can be duplicated in cities that are in fairly close proximity without encountering unacceptable interference . This protection is much harder to achieve where skywave propagation may permit an interfering signal to be heard at a great distance.


Shortwave radio

Shortwave radio services may change frequency often as the ionosphere's reflectivity varies. Unlike domestic broadcast stations that stay on a single assigned frequency, shortwave broadcast stations move frequency to take advantage of hour-to-hour and season-to-season changes in the ionosphere. As the 11-year sunspot cycle waxes and wanes, shortwave stations the world around move to shorter wavelengths when there are more sunspots and to longer wavelength bands when sunspots are minimal.

Listening to shortwave radio requires more effort than istening to local domestic radio. The best frequencies to search change from one hour to the next throughout the day. Due to the effect of the sun, shortwave signals sometimes may disappear for days at a time, then reappear with astounding strength. Many shortwave stations do not broadcast at all hours of the day. In addition, a station must be targeting your part of the world specifically; otherwise the signal will probably be weak.


Regulation of radio transmissions

The part of the electromagnetic spectrum that can be used for radio communication cannot accommodate everyone who might wish to use this resource. Access is controlled and technical standards are enforced by law. With few exceptions, radio transmissions are permitted only as authorized by licenses.

Since 1934 in the United States, licensing and equipment approval has been the responsibility of the Federal Communications Commission. Similar regulation is the rule in other countries. Technical standards are required by radio regulation. Just as traffic laws improve highway safety, laws and regulations that encourage the fair use of the limited radio spectrum help to avoid conflicts between users.


The future of radio

Radio broadcasting now includes a newer, better digital system known as DAB, digital-audio broadcasting. Early tests indicate that a switch to digital imparts compact-disc quality to radio programming. There are two possible modes for DAB. In Europe , completely new stations on a different band of frequencies is favored. In the United States it seems probable that digital information will transmitted as information superimposed on the programming modulation now used. The digitized audio can be so much lower in power than the "main" programming that it will be inaudible to listeners with analog receivers. Early program tests of this system have been successful and increases in audio quality have been significant.


Resources

books

The 1995 ARRL Handbook. The American Radio Relay League, 1995.

Hobson, Art. Physics: Concepts and Connections. New York: Prentice-Hall, Inc., 1995.

Jacobs, George, and Theodore J. Cohen. The Shortwave Propagation Handbook. Cowan Publishing Corp., 1970.

Ostdiek, Vern J., and Donald J. Bord. Inquiry Into Physics. St. Paul: West Publishing Company, 1995.


other

Now You're Talking. The American Radio Relay League, 1994.


Donald Beaty

KEY TERMS


. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Antenna

—An electrical conductor used to send out or receive radio waves.

Capacitor

—Electrical component that cancels magnetic property of wire.

D Layer

—Arbitrary designation for the lowest layer of the ionosphere.

Electric field

—The concept used to describe how one electric charge exerts force on another, distant electric charge.

Electron tube

—Active device based on control of electrons with electric fields.

F layer

—Arbitrary designation for the highest layer of the ionosphere.

Gamma ray

—Electromagnetic radiation with the shortest wavelengths.

Inductor

—Electrical component that adds magnetic property to wire.

Infrared light

—Light with wavelengths longer than those of visible light.

Ionized

—Missing one or more electrons, resulting in a charged atom.

Magnetic field

—Effect in space resulting from the motion of electric charge.

MegaHertz

—One million cycles per second; MHz.SI abbreviation for MegaHertz.

Morse code

—Dot and dash code used to send messages over telegraph wires.

Resonance

—The enhancement of the response of a system to a force, when that force is applied at a particular frequency known as the resonant frequency.

Selectivity

—Receiver property enabling reception of only wanted signals.

Sensitivity

—Receiver property enabling reception of weak signals.

Standing wave

—A stationary pattern of activity resulting from interference.

Sunspot

—Cooler and darker areas on the surface of the sun. They appear dark only because they are cooler than the surrounding surface. Sunspots appear and disappear in cycles of approximately 11 years.

Telemetry

—Engineering and scientific measurements transmitted by radio.

X ray

—Electromagnetic radiation of very short wavelength, and very high energy.

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Radio

Radio


For three-plus decades beginning in the early 1920s—before the mass marketing and mass popularity of television—radio was the foremost in-house leisure activity and information-gathering source for millions of Americans. Radio had a profound influence on popular culture. Not only did radio record historical events for posterity, but it forever altered the manner in which information and entertainment were disseminated to the public. Television (see entry under 1940s—TV and Radio in volume 3) captures both the eyes and the ears and tends to shut out other senses; it is called a passive medium because viewers tend to become absorbed in watching it and do little else. Radio, however, is an active medium, engaging only the sense of hearing; it allows listeners to use their imagination to conjure up a picture in their minds.

The genesis of radio dates to the 1890s, when Italian inventor-physicist Guglielmo Marconi (1874–1937) pioneered the use of wireless telegraphy. In 1895, Marconi first was able to transmit radio waves short distances; four years later, he succeeded in transmitting a signal across the English Channel. In 1906, American Lee De Forest (1873–1961) furthered the development of the medium by inventing the triode, an electron tube that featured three electrodes (anode, cathode, and grid). His triode made modern radio broadcasts possible. In 1920, KDKA in East Pittsburgh, Pennsylvania, the initial radio station, began broadcasting. At the time, only five thousand Americans had radio receivers. The question of the day—who would pay for radio?—was answered two years later when New York station WEAF broadcast the initial paid radio commercial. Soon radio stations were sprouting up across the country, with the first major radio networks, NBC and CBS, coming into being in 1926 and 1927. By the beginning of the Great Depression (1929–41; see entry under 1930s—The Way We Lived in volume 2) in 1929, the essence of popular radio programming was in place. The standard radio format consisted of music, news, and entertainment programs, with paid advertisements liberally sprinkled in between. By the early 1930s, 90 percent of Americans owned at least one radio.

Radio's golden age arrived during the 1930s, with an ever-expanding variety of programming. Some programs featured specific story lines: dramas, comedies, soap operas, Westerns, and romances. Others were variety shows, featuring musical performances and comedy skits. The latest popular songs and rhythms were broadcast live from hotel ballrooms, where the era's top Big Bands were performing. Hollywood stars regularly reenacted their movie roles on radio, with the purpose being to keep them and their films in the public consciousness while promoting their upcoming projects. Indeed, radio—just like movies—proved to be a great escape for the millions of Americans then suffering the ravages of the Depression.

Dozens of the most popular television shows from the 1950s and 1960s started out on radio. These included lawyer series Perry Mason (1943–1955 [radio]; 1957–1966 [television]; see entry under 1930s—Print Culture in volume 2); Western dramas The Lone Ranger (1933–1955 [radio]; 1949–1957 [television]; see entry under 1930s—TV and Radio in volume 2) and Gun-smoke (1952–1961 [radio]; 1955–1975 [television]; see entry under 1950s—TV and Radio in volume 3); and comedy show The Jack Benny Program (1932–1955 [radio]; 1950–1965 [television]). Other TV series were derived from radio shows: I Love Lucy (1951–1957; see entry under 1950s—TV and Radio in volume 3), the most celebrated of all 1950s situation comedies, evolved from My Favorite Husband (1948–1951). Many of the most popular radio stars were comedians and comic actors: Benny (1894–1974); the husband-and-wife team of George Burns (1896–1996) and Gracie Allen (1902–1964); Fred Allen (1894–1956); Bob Hope (1903–); and ventriloquist Edgar Bergen (1903–1978). A typical radio situation-comedy was Fibber McGee and Molly (1935–1957; see entry under 1930s—TV and Radio in volume 2). Meanwhile, Norman Corwin (1910—) and Arch Oboler (1909–1987) pioneered the development of radio drama. Among the many popular dramatic radio programs: Gangbusters (1936–1957); Suspense (1942–1962); Inner Sanctum (1941–1952); and The Shadow (1930–1954; see entry under 1930s—Print Culture in volume 2).

Easily one of the most famous radio broadcasts came on October 30, 1938. Orson Welles (1915–1985), who later became famous as a film director, staged the science-fiction classic The War of the Worlds (see entry under 1930s—TV and Radio in volume 2) by H. G. Wells (1866–1946). Author Wells's story involves an invasion of Earth by Martians. Director Welles's production was realistically rendered; it was presented in real time, with an announcer declaring, "Ladies and gentlemen, we interrupt our program of dance music to bring you a special bulletin from the Intercontinental Radio News." As a result, untold number of listeners actually believed that New Jersey was being invaded by Martians.

Radio did more than entertain its listeners. On Sunday mornings, preachers sermonized over the airwaves. Most were simply preaching to their flock, but one became infamous. He was Father Charles Coughlin (1891–1979), the "radio priest" of Royal Oak, Michigan, whose audience during the 1930s numbered in the millions and whose radio sermons became increasingly anti-Jewish and pro-Fascist (in favor of direct government suppression of different viewpoints). Meanwhile, beginning in 1933 and lasting until his death, President Franklin D. Roosevelt (1882–1945) wisely used radio to speak directly to U.S. citizens. Some of his speeches were labeled "fireside chats." Utilizing the intimacy that radio creates, he opened each broadcast with the phrase "My dear friends. . ." and went on to explain his policies and programs in an attempt to elicit public support. Radio also played a critical role in the American public's perception of World War II (1939–45). The legendary reports by CBS broadcast journalist Edward R. Murrow (1908–1965), made during the 1940 German bombing of London, helped solidify public opinion in favor of the Allies. After America's entry into the war, in the wake of the December 7, 1941, surprise attack by the Japanese on Pearl Harbor, radio brought the war directly into every American household. Radio journalists reported directly from the war's hot spots.

In the 1930s, regulation became an important aspect of radio broadcasting. At the beginning of the decade, stations often interfered with the programs of other stations by broadcasting on the same bandwidth. By 1934, the U.S. government created the Federal Communications Commission (FCC), whose charge was to organize stations in such a way that broadcasts could play across the country without overlapping. The FCC also fore-saw the danger of having an entity in control of too many stations in one geographic area, thereby having too much control over what information the listeners heard. The FCC then sought to limit the number of radio outlets a company or an individual could own.

With the invention of television and the marketing of television sets in the post–World War II era, radio slowly began to lose its standing within the American home. Radio held onto a listening audience in the 1950s and 1960s as the primary medium for marketing to teenagers the latest Top 40 (see entry under 1950s—Music in volume 3) rock and roll (see entry under 1950s—Music in volume 3) hits. In the late 1960s and 1970s, the rise of FM stations and the free-form experimentation of FM disc jockeys (see entry under 1950s—Music in volume 3) helped propel the cultural influence of rock music. In the 1990s, a generation of popular and controversial "talk radio" (see entry under 1980s—TV and Radio in volume 5) personalities emerged. Among them were the "tough-love" advocate Dr. Laura Schlessinger (1947–); abrasive arch-conservative Rush Limbaugh (1951–); and shock radio (see entry under 1980s—TV and Radio in volume 5) disc jockey Howard Stern (1954–).

—Rob Edelman

For More Information

Bray, John. The Communications Miracle: The Telecommunications Pioneers from Morse to the Information Superhighway. New York: Plenum Press, 1995.

Empire of the Air: The Men Who Made Radio (film). Florentine Films, 1992.

Finkelstein, Norman H. Sounds in the Air: The Golden Age of Radio. New York: Maxwell Macmillan International, 1993.

Hilmes, Michelle. Radio Voices: American Broadcasting, 1922–1952. Minneapolis: University of Minnesota, 1997.

Ladd, Jim. Radio Waves: Life and Revolution on the FM Dial. New York: St. Martin's Press, 1991.

MacDonald, Fred J. Don't Touch That Dial: Radio Programming in American Life, 1920–1960. Chicago: Nelson-Hall, 1979.

Maltin, Leonard. The Great American Broadcast: A Celebration of Radio's Golden Age. New York: Dutton, 1997.

Nachman, Gerald. Raised on Radio. New York: Pantheon Books, 1998.

Radio Days (film). Orion Pictures, 1987.

Ryan, Thomas. American Hit Radio: A History of Popular Singles from 1955 to the Present. Rocklin, CA: Prima Publishing, 1996.

Smulyan, Susan. Selling Radio: The Commercialization of American Broadcasting, 1920–1934. Washington, DC: Smithsonian Institution Press, 1994.

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Radio

Radio

Radio was one of the great forces behind social and political mobilization in the twentieth century. Joseph Goebbels, one of Adolf Hitler's earliest and most enthusiastic supporters, understood the potential power of this media. When Hitler rose to power in 1933, he appointed Goebbels as his minister of propaganda; in this role, the latter displayed his talents, particularly where radio broadcasts were concerned. Under Goebbels's leadership the Nazis subsidized the production and distribution of millions of cheap radios in order to strengthen their grip on the population. Goebbels's first radios were deliberately designed with a limited range so that they would not pick up foreign transmissions. At the beginning of World War II over 70 percent of all German households owned a radio, the highest percentage in the world.

The extent to which Nazi radio broadcasts played a clear role in preparing and then swaying German public opinion toward the extermination of the Jews is hard to evaluate. Like the press or cinema, radio was one of the media used to diffuse anti-Semitic themes. In the early years of the Nazi regime the radio called for a boycott of Jewish shops. However, not a single radio program with a specific theme of anti-Semitism was designed. Entertainment programs did not include such messages. Of course, speeches given by Hitler and other Nazi leaders containing angry passages condemning the Jews were routinely broadcast on the radio. On the eve of Kristallnacht (Night of broken glass) on November 9, 1938, Goebbels used the radio to urge the German public to pillage Jewish shops and burn down synagogues. During World War II the Nazi media repetitively depicted Jews as devilish characters responsible for the soon worldwide conflict but they continued to keep their extermination a secret.

Some fifty years later the radio was used in a much more direct way to set the stage for and then perpetrate genocide in Rwanda. Within the context of civil war, initiated in October 1990 by the Tutsi-dominated Rwanda Patriotic Front (RPF), Hutu extremists decided to create their own radio station. Their intention had been to counteract the RPF broadcasts (Radio Muhabura) and those of the official national station (Radio Rwanda) the latter was indeed considered too moderate and had simply become an outlet for the new multiparty government by 1992. This project, driven by the historian Ferdinand Nahimana who had been dismissed from the Rwandan Office of Information (ORINFOR) that supervised Radio Rwanda, commenced in April 1993 with the creation of Radio Télévision Libre Mille-Collines. This new station was formally independent, but in fact influential politicians belonging to the president's entourage, some of them related by marriage, supported it. As in Nazi Germany, many cheap radio receivers were distributed to the population in different regions of the country. Starting in August 1993 the station broadcast rousing Zairian music popular among Rwandans, and the station became rapidly renowned. RTLM presented itself as an interactive radio station, giving listeners the opportunity to speak to the Hutu people by calling into the station.

This broadcasting format was new to Rwanda at that time. RTLM attracted the populace with its candor and humor, but its ideological message was clear: It was the voice of the Hutu people, victims of the profiteering elites, of calculating Tutsis and those who betrayed the Hutu cause. After the Hutu president of Burundi, Melchior Ndadaye, was killed on October 21, 1993, RTLM programming became still more aggressive. All day long the station repeated a political jingle that prompted its audience to wait: "We have hot news," the broadcasters would proclaim, and when the news was finally diffused, listeners would hear a series of vicious anti-Tutsi slogans. Several times a day the station also broadcast songs written by the Hutu extremist Simon Bikindi.

Immediately after the assassination of the Rwandan president, Juvenal Habyarimana, on April 6, 1994, RTLM openly called for the massacre of Tutsis, Hutu opponents, and even Belgian peacekeepers. Hutu extremists used their radio station to ridicule those in the local administration who called for calm. From April to June 1994 RTLM helped mobilize the Hutu population in support of the killing of the Tutsi minority. The radio station even dared to name the Tutsis who remained to be killed. For the first time in history radio was used to directly perpetrate genocide.

The role of radio in the killings must not be overestimated, however. Numerous massacres were committed without the direct influence of RTLM. Military officers, militia leaders, and mayors who supervised Hutu peasants on the ground played a crucial role in organizing the population to kill. Nevertheless, it is evident that radio, the main media in a country where newspapers are hardly read and television remains in short supply, played an important role in the diffusion of racist anti-Tutsi ideology. RTLM provided Hutu extremists with a useful communications tool that reinforced their political influence over the people. Radio can be a most formidable weapon, in particular when introduced to a population already weakened by fear. Words conveyed over the radio may thus turn deadly.

SEE ALSO Incitement; Propaganda; Radio Télévision Libre Mille-Collines; Rwanda; Television

BIBLIOGRAPHY

Chalk, Frank (1999). "Hate Radio in Rwanda." In The Path of a Genocide, ed. Howard Adelman and Astri Suhrke. New Brunswick, N.J.: Transaction Publishers.

Chrétien, Jean-Pierre, ed. (1995). Rwanda. Les médias du génocide. Paris: Karthala.

Marszolek, Inge (1998). Zuhoeren und Gehoertwerden. Vol. 1: Radio im Nationalsozialismus, ed. Adelheid von Saldern. Tuebingen: Diskord.

Jacques Semelin

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Radio

RADIO

Radio includes a broad group of technologies that utilize electromagnetic radiation (also called radio waves) to transmit and/or receive information. Examples of radio technologies can be drawn from numerous industries, applications, and end users. A partial listing would include radio (and television) broadcasting, maritime communications, radio navigation, cellular telephony, satellite communications, numerous military applications, wireless computer networking, noncontact identification systems, military and meteorological radar, global positioning systems, and radio astronomy (see Figure 1).


What all these systems have in common is the conversion of electrical energy from one form into another, specifically, from electrical currents bound in conductive materials such as wires and cables into unbounded electromagnetic radiation that is free to propagate through space, the atmosphere, or another nonconducting medium. This is the process of radio transmission. Radio reception is the reverse process, in which incoming electromagnetic radiation is converted into electrical currents in the antennas, wires, and components of a radio receiver.


Historical Developments

The following material is a brief history of the development of radio technology with an emphasis on related ethical, political, and legal issues. This history draws on Christopher Sterling and John Michael Kittross's Stay Tuned (2002).

The background of radio was the earlier practical development of wired electronic signal transmission and reception, as in the telegraph (1830s and 1840s) and James Clerk Maxwell's electromagnetic theory (1860s), which was confirmed by Heinrich Hertz's laboratory experiments (1880s). It was his ability to draw on those previous achievements that enabled Guglielmo Marconi (1874–1937) (see Figure 2) to transmit and receive the first wireless telegraph messages in 1895, an experiment that he followed up with wireless transmissions across the English Channel (1899) and the Atlantic (1901).

The rapid development of radio led in 1910 to the Wireless Ship Act in the United States, which required a radio and an operator on all oceangoing passenger vessels. Through World War I the U.S. Navy continued to control radio facilities, while the U.S. Congress debated the future government role in relation to the new technology. Shortly after the war, in 1921, thirty broadcasting stations went on the air, using only two frequencies or channels.

In 1922 President Herbert Hoover hosted the first radio conference, which called for government regulation of radio technology, limited advertising, and classification of radio stations by the services they provided. Two years later the British physicist Sir Edward Victor Appleton conducted the first experiment with radio range-finding equipment, reflecting radio waves off the ionosphere to determine its height. This was an important step in the development of radar.

Later in the 1920s President Calvin Coolidge signed the Radio Act of 1927, establishing the Federal Radio Commission (FRC). In that decade the National Association of Broadcasters issued a code of radio advertising and programming ethics.

In 1932 the engineer Karl Jansky discovered a strong source of radio noise that later was discovered to originate outside the solar system; this marked the beginning of radio astronomy. In 1934 the Federal Communications Commission (FCC) was established to replace the FRC. Later in the decade, in 1937, the first practical mobile radio, the DR38a transmitter-receiver, was developed.

During World War II both Axis and Allied engineers made significant advances in land, mobile, maritime, and airborne radio as well as radar. After the war, in 1948, scientists at Bell Laboratories demonstrated the potential uses of the transistor. Between 1945 and 1960 numerous television stations began broadcasting coast to coast, linked by microwave radios.

The year 1958 marked the invention of the integrated circuit. In the 1960s the concept of a broadband mobile telephone system was outlined. In 1969 the first frequency-resuing commercial cellular system was used on trains running from Washington to New York. By the 1980s analog cellular telephone use had become widespread. Digital cellular systems with increased capacity were introduced in the 1990s. Another significant development was the FCC auction of spectrum for the Personal Communications Services (PCS) band.

The Radio Frequency Spectrum as a Limited Natural Resource

The electromagnetic spectrum contains frequencies from below 1 Hertz (one cycle per second) to above 1025 Hz. However, a much smaller subset of those frequencies lend themselves to terrestrial radio systems. Although there is not universal agreement on the boundaries, the "radio spectrum" is the subset of the electromagnetic spectrum with frequencies from 100,000 Hz to 100 GHz (105 to 1011 Hz).

The lower end of the radio spectrum is less suited for most communications applications. The rate at which information can be transmitted (the data rate) becomes lower as the frequency decreases. This does not mean that low-frequency waves travel through space more slowly because all electromagnetic radiation travels at the speed of light. However, the theoretical rate of information transfer decreases with decreasing frequency. This gives rise to a lower limit to the frequency band that can be used for most radio systems. Additionally, the ionosphere becomes opaque at lower frequencies, limiting some applications, although enhancing others.

At higher frequencies the entire atmosphere (not just the ionosphere) becomes opaque except for a few "windows" in which electromagnetic radiation is free to propagate without being absorbed significantly (see Figure 3). There is an optical window (the atmosphere is transparent to the frequencies human eyes can detect), and there is a radio window. Transmission of signals at frequencies above this window are absorbed or scattered rapidly by the atmosphere, similarly to the way fog limits visible frequencies. The opaque nature of the atmosphere at higher frequencies establishes an upper limit to the radio spectrum; thus, the radio spectrum is capped in its upper and lower ends. This means that the radio spectrum is a limited natural resource. Because of its immense importance and finite nature, the radio spectrum presents significant distributive justice issues.

Ethics, Politics, and Law

The ethical, political, and legal aspects of radio can be arranged in a four-fold taxonomy. Although there is significant overlap amongst the categories, they are useful in conceptualizing the major issues and highlighting the important ethical traditions pertaining to radio development and use.

First, there are issues surrounding the technological development of radio that pertain to topics in engineering ethics. For example, the use of radio for military applications and growing concerns about the health effects of electromagnetic frequencies present ethical challenges to engineers who are responsible for upholding the safety, health, and welfare of the public.

Second, radio content and use issues instantiate several aspects of broadcast journalism ethics as they place responsibilities on program directors, journalists, and radio managers. These obligations are traditionally formalized in codes of ethics such as the NAB code of radio advertising and program ethics and the Radio-Television News Directors Association (RTNDA) code of ethics, which states that electronic journalists ought to serve as trustees of the public reporting the truth with fairness, integrity, and independence.

Third, the broader cultural and societal impacts of radio raise issues explored in the philosophy of technology and the field of Science, Technology, and Society (STS) studies. Radio technologies reciprocally interact with various elements of culture to co-produce societal changes and personal life experiences. In the United States, for example, conservative talk radio programs have exerted massive influence over the political landscape and Christian programming has also come to dominate certain markets, which has influenced conceptions about religion in the public sphere. Such developments underscore the idea that radio is not a neutral medium, but rather an active agent that is used to selectively broadcast some voices and messages rather than others. It is a political and cultural force, albeit somewhat eclipsed by television. Interestingly, the rise of opinion and advocacy programs on radio seemed to foreshadow a general shift in media (furthered by the Internet and the "blogosphere") away from trust in a few supposedly neutral broadcast centers to a variegated spectrum of information streams.

Lastly, questions of how radio should be used and regulated raise fundamental issues from political philosophy such as distributive justice, the proper relationship between government and private enterprise, censorship and the proper limits to freedom of speech, and the concentration of corporate control over media.

As a common resource, it has been widely maintained that the radio spectrum must be centrally regulated to insure fairness and efficiency. For example, the International Telecommunication Union (ITU) is a regulatory body within the United Nations system that helps coordinate global telecommunications networks and services. Additionally, each country has its own national frequency allocation plan. In Germany, for example, each state exercises its own authority over radio broadcasting rather than a centralized federal entity. In the United States that plan is administered by the FCC. The FCC is an independent government agency, directly responsible to Congress, which plans, allocates, and monitors the use of the radio spectrum for nongovernment users. FCC rules pertaining to free speech and censorship tend to raise the most public controversy, especially those relating to indecency, obscenity, and profanity. These rules do not apply to satellite and cable broadcasting. The National Telecommunications and Information Administration (NTIA) is responsible for the allocation and assignment of frequencies for use by the federal government The national frequency allocation plan divides the spectrum into a multitude of frequency bands, reserving bits of spectrum for different types of users and reducing channel interference. It plays a vital role in balancing the often conflicting needs of commercial, military, scientific, and educational uses.

Although some level of government regulation may be necessary, many advocate further deregulation in order to capture the benefits of market competition and avoid inefficiency, corruption, or other unethical practices by centralized bureaucrats. Others, however, fear that deregulation will lead to further corporate monopolization of local markets. In the United States, concerns are developing that the increased corporate consolidation of radio diminishes its locality, threatens the democratizing value of free and independent communication, homogenizes music play lists, and undermines journalistic quality.

Similar debates about the proper roles of private and public or community radio sparked the 1967 creation of the U.S. Public Broadcasting Act, which established the Corporation for Public Broadcasting (CPB). The CPB receives annual appropriations from Congress to support independent local stations and National Public Radio (NPR), which was established in 1970. Although this helps defend the independence, integrity, and diversity of radio journalism, it also raises accountability issues about the use of federal funds.

College and community listener sponsored radio stations also attempt to secure independence and diversity at the fringes of corporate media conglomerations. In 2000, the U.S. government began issuing licenses for low-power (below 100 watts) radio stations partially to provide another avenue for local communities (especially low-income and minority) to obtain diverse, community-oriented information. Most of these licenses have been obtained by rural communities and churches, and they have not had the expected impact on urban areas that are most dominated by commercial radio. Concerns have been raised that Christian stations are monopolizing these markets, thus producing the same drawbacks from consolidation. There is also some concern that these stations interfere with broadcasts from bigger stations. Furthermore, many low-power radio broadcasts still operate illegally as "pirate" stations. Some of these stations are switching to internet broadcasts in attempts to avoid federal lawsuits.

Current Trends

As more uses of radio technologies are conceived, developed, and marketed (e.g., cell phones and wireless internet connections) and as demand for existing uses continues to grow, the radio spectrum will become increasingly crowded. Interference among users will become increasingly difficult to avoid and solve. Modulation schemes that are more tolerant of interference such as spread spectrum–based technologies should see increased use, as should hardware-based solutions such as more sophisticated filtering. Spectral crowding also will result in the continued migration toward higher frequencies despite the greater atmospheric attenuation and other technological obstacles. Finally, both the general public and those involved in the technical industries will be forced to become more aware of the limits of the radio spectrum, the importance of coordination and regulation, issues involving radio interference, and spectral crowding.


J. BRIAN THOMAS

SEE ALSO Advertising, Marketing, and Public Relations; Communication Ethics; Communication Systems; Entertainment; Networks.

BIBLIOGRAPHY

Kobb, Bennett. (2001). Wireless Spectrum Finder: Telecommunications, Government, and Scientific Radio Frequency Allocations in the U.S., 30 MHz–300 GHz, 6th edition. New York: McGraw-Hill.

Kraus, John D. (1986). Radio Astronomy, 2nd edition. Powell, OH: Cygnus-Quasar.

Radio Astronomy: Observing The Invisible Universe. (1999). Video. Produced by Dick Young Productions, New York, NY, for the National Science Foundation, USA.

Reed, Dana George, ed. (2001). The ARRL Handbook for Radio Amateurs. Newington, CT: American Radio Relay League.

Sterling, Christopher H., and John Michael Kittross. (2002). Stay Tuned: A History of American Broadcasting, 3rd edition. Mahwah, NJ: Lawrence Erlbaum.

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Radio

RADIO.

BIBLIOGRAPHY

A medium of mass communication with great immediacy, radio proved a major catalyst of social and political change in twentieth-century Europe. Radio grew from research pioneered by many European scientists, including the Scotsman James Clerk Maxwell (1831–1879), the German Heinrich Rudolph Hertz (1857–1894), the Russian Alexander Stepanovich Popov (1859–1906), and the Italian Guglielmo Marconi (1874–1937), who patented a wireless telegraphy device in 1900. Rival claims to be the inventor of radio had some propaganda significance later in the century. The device was initially used for maritime communication. Experimental audio transmissions included a series of weekly live concerts broadcast from the Belgian royal palace at Laeken from March to 20 August 1914, over what was then known as TSF (télégraphie sans fil, or wireless telegraphy). A new medium was taking shape, only to be interrupted by the coming of World War I.

During the early 1920s entrepreneurs in many European countries founded radio stations. The first major station was that of the Nederlandse Radio Industrie, founded in Holland in 1919, a year before the Westinghouse station KDKA began broadcasting in Pittsburgh, Pennsylvania. The Dutch company Philips also played a leading role in the mass production of radio equipment. Danmarks Radio began in Denmark in 1920 and had a monopoly from 1926. November 1922 brought inaugural broadcasts by both Radiola (later Radio Paris) in France and the British Broadcasting Company (later Corporation) from London. The first regular Czechoslovakian broadcasts began in May 1923, and Germany's first official radio station, Radiostunde Berlin (later Funkstunde Berlin), began broadcasting in October 1923. Belgian commercial broadcasts also began that year. In the mid to late 1920s many European countries founded state-run corporations to regulate and direct the new medium. Examples included the Yleisradio (General Broadcaster) in Finland in 1926 and the BBC in 1927. The Belgian government founded a public radio station in 1930.

In March 1927 Radio Netherlands began short-wave broadcasts to the Dutch East Indies and ushered in European external services. Major services included Radio Moscow and Deutscher Kurzwellensender (from Zeesen, near Berlin), both founded in 1929; Vatican Radio, founded in 1931; and BBC Empire Service in 1932. Swiss Radio International began in 1935 and Radio Prague's external services began in 1936. Some international services were purely commercial, such as the English-language broadcasts by Radio Normandy (1926–1939) or the multilingual Radio Luxembourg, launched in 1933.

Radio had an immense social impact on inter-war Europe, providing the cultural glue to cement national consciousness and bringing the outside world closer as never before. The medium soon acquired a political significance as the ideal platform for the demagogic leaders of the era, most notoriously Benito Mussolini in Italy and Adolf Hitler in Germany. Hitler, who much preferred speaking to live audiences, once remarked that without radio and other modern methods of communication there would have been "no victory for National Socialism." Following the Nazi conquest of Europe, the great radio stations of the region became channels of Nazi propaganda, while the BBC in London provided a home from which governments in exile could broadcast to their occupied countries. For most of the war the British government took care to avoid inciting armed rebellion that would merely lead to the futile loss of life. The British Political Warfare Executive created a number of "black" propaganda radio stations, including one that purported to be a station run by German soldiers hostile to Hitler, designed to sow division within the Nazi state.

During the postwar years radio was both a medium of Americanization within Western Europe and a route to challenge the Soviet domination of Eastern Europe. The United States government broadcast to all of Europe over the Voice of America, and sponsored politicized broadcasts to Eastern Europe over Radio Free Europe (founded in 1950) and its sister station aimed at Russia, Radio Liberty. In Berlin the Americans operated a station called Radio in the American Sector, and in Austria they established Radio Rot Weiss Rot (Red White Red). No less significantly, Europeans could tune in to hear American pop music on the stations of the Armed Forces Network, created to serve American servicemen garrisoned in Europe. European stations also played their role in the radio cold war, with Deutsche Welle (relaunched in 1953) and the BBC World Service attracting substantial audiences in the Eastern bloc. It is significant that the first target for Polish anticommunist rioters in 1956 was the government station that jammed Western broadcasts; however, the Hungarian rising of 1956 underlined the danger of encouraging open rebellion, as Radio Free Europe had done.

European state broadcasters, bound by regulations designed to protect live music from competition from recording, were slow to respond to audience interest in American and American-inspired music. This created a niche for pirate radio stations such as Radio Mercur, which broadcast from international waters off Denmark and Sweden from 1958 to 1962, or Radio Caroline, which broadcast from the North Sea to Britain from 1964 to 1967. In the 1960s many European countries modernized their domestic broadcasting to include more music but also to protect cultural and spoken-word programming. In 1965 the three French radio stations France I, II, and III rebranded as France Inter, France Musique, and France Culture, while in 1967 in Britain the BBC created its first pop music station, Radio One, and rebranded its light program, third program, and home service as Radios Two, Three, and Four. In 1981 the victorious candidate for the presidency of France, François Mitterrand, made the deregulation of French broadcasting a major campaign promise and swiftly delivered reform.

In the 1980s radio played a major role in the political changes between East and West, with Western radios challenging the communist control of the media and ensuring that each country in the region knew about the march of reform in its neighbors. The process reached its climax in 1989. Radio remained significant as Yugoslavia fragmented. Station RTS Belgrade became a mouthpiece for the nationalist dictator Slobodan Milosevic, while a youth-oriented rock music station founded in 1989 called B92 opposed the regime. B92 weathered intimidation and various bids to close it down, and in 2000 the station played a major role in rallying opposition to Milosevic in the election.

See alsoCinema; Radio Free Europe; Television.

BIBLIOGRAPHY

Briggs, Asa. The BBC: The First Fifty Years. Oxford, U.K., 1985. A concise history of the British Broadcasting Corporation.

Collin, Matthew. This Is Serbia Calling: Rock' n' Roll Radio and Belgrade's Underground Resistance. 2nd ed. London, 2004. A case study of radio in Yugoslavia.

Historical Journal of Film, Radio and Television (1981–)

Journal of Radio Studies (1992–).

Wagnleitner, Reinhold. Coca-Colonization and the Cold War: The Cultural Mission of the United States in Austria after the Second World War. Translated by Diana M. Wolf. Chapel Hill, N.C., 1994. A seminal study of American cultural propaganda in postwar Austria.

Nicholas J. Cull

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