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Definition: radio from The Penguin Dictionary of Science

The transmission and reception of electromagnetic radiation of ➤radio frequency. Its primary application is for communication. A signal is broadcast on a radio-frequency ➤carrier wave by ➤modulation, and is demodulated at the receiver.


Summary Article: Radio
from Encyclopedia of Global Studies

Radio was the first global electronic medium. It dominated public communications on local, national, and global levels in the 20th century, and it continues to be an important feature of the public media of the 21st century. The term radio has two meanings: It describes the content that is made to be listened to when a radio apparatus is tuned to a favorite radio station as well as describes the apparatus itself. The latter meaning is so linguistically embedded that it persists across the several digital platforms on which radio programs can now be received. The word has long been detached from its technological derivation.

Radio arrived in its public form in the 1920s as the first of the electronic mass media that collectively became a dominant force in shaping political, social, economic, and cultural life around the world through the 20th century. The transformative effect of radio broadcasting was that for the first time one human being could speak directly and over great distances to many dispersed individuals in their own homes, simultaneously and instantaneously. The experience of copresence, the novel act of listening in private while conscious of the mass of others listening in the same moment, may be part of radio's enduring appeal. Prior to its organization into a public medium, the prime value of the technology had been providing point-to-point communication, which greatly extended the capabilities of naval, military, and emergency services. It should not be forgotten how pervasive and influential that nonpublic application has been internationally over time. However, in all but the most isolated populations in the world, it is as a part of the public realm that radio has become fixed in public consciousness.

Analog Radio

The original conceptualization of radio was as a unified, global system, taking advantage of a universal resource, the segment of the electromagnetic spectrum that became known as radio waves. Its component technologies emerged in an era when cables were being laid to link nations and continents via point-to-point Morse telegraph communication.

The properties of the long (LW), medium (MW), and short (SW) wave bands employed in the earliest organized transmission system, amplitude modulation (AM), were particularly suited to these national, international, and intercontinental uses. National coverage could be achieved with few MW transmitters or fewer LW transmitters; and SW frequencies could carry huge distances around the curvature of the Earth, making them especially suitable for international broadcasting. Of the three wave bands, MW achieved the better overall sound quality and became the preferred wave band for musical entertainment. Thus, most stations known today in popular terminology as AM radio are found on MW.

During the 1960s, AM was joined by a parallel system of frequency modulation (FM). Also known as VHF, from the very high frequency radio wave band it used, it offered higher fidelity than AM and the possibility of transmitting in stereo. However, because VHF carries over shorter distances, it requires more transmitters and is thereby better suited for localized broadcasting, such as across an urban area.

Three main technical factors converged to impel the worldwide adoption of FM: a reinvention of radio's role in the developed world forced by its usurpation at the heart of the domestic social space by the television set; the opportunity, offered by the invention of the transistor and the mass-produced circuit board, for radio to exit that social space and move into private, more individualized spaces; and the demand thus created for more frequencies to be made available to increase the choice of listening as audiences became more differentiated. Socioeconomic components of this rapid repositioning of the medium were the postwar economic boom, led by the United States, which provided the purchasing power not only for television sets but also for private cars, into which radios could now be fitted as standard. Affluence extended to a wholly new youth market with leisure time to fill and identities to formulate, the expression of which was focused particularly on consumption of the products of a burgeoning transatlantic popular music industry, for which FM music radio provided strong identification and promotion.

Digital Platforms

The incursion of digital technologies since the 1990s has been additional to analog radio broadcasting rather than replacing it. The technical advantage of digitization is that “encoded” audio data travel with much greater efficiency and flexibility than their analog counterparts, whether through wired telecoms networks or through the air via satellite or terrestrial transmitter. Radio today is listened to on all of these platforms, although each has limitations.

The rapid acceptance of World Wide Web protocols as a universal standard has certain parallels with the uncontested early adoption of AM radio. And the inclusion of protocols for streaming live audio has allowed most broadcast stations also to simulcast their live output on the Internet, alongside the many online-only stations. On the Web, any station can extend its reach in space, becoming global, and also in time, by making programs available on its website to play on demand or download after their scheduled broadcast. However, penetration of the Internet in many parts of the world is much less than FM/AM and portability is, so far, limited.

By contrast, the absence of a consensus on an international standard for a digital counterpart to analog terrestrial broadcasting means that different countries are adopting competing, noncompatible systems. As of 2010, therefore, no global market exists for digital radio receivers, which thus far limits the rate of penetration.

Organization: A Local, National, or Global Medium

By 1930, most countries had at least one radio station on the air. Governments thus needed to decide how to manage the radio spectrum for public and nonpublic use, both within their own borders and so as to avoid interference with neighboring countries. International coordination of radio broadcast frequencies has, since the Washington Conference of 1927, been agreed on and regularly updated through what is now an agency of the United Nations, the International Telecommunications Union (ITU) Radiocommunication Bureau. Within the agreements made here, governments determine their own policies for licensing radio stations internally. Two overarching approaches to organizing radio emerged, according to whether stations were funded publicly or commercially. Many countries by now operate a mixture of both and incorporate a third tier of licenses based in the voluntary sector but with the legacy effects of their original model still in evidence. Which model a nation chose was inevitably a matter of ideology.

The Sectors of the Radio Industry
Publicly Financed National Services

Most countries began by adopting some variant of public funding to support the development of radio. At one end of this spectrum, Russia established the archetype of state radio, designed explicitly to educate its population into a particular way of thinking. In 1921, shortly after the Soviet government came to power, it set up a broadcast organization to create the content and the infrastructure through which the bulletins of news and state information were first heard. At the other end of the spectrum is the model devised by the British government and the British Broadcasting Corporation (BBC) in 1926. This also created a national monopoly broadcaster but one separated from government by means of its funding mechanism in the form of an annual license fee for owners of a radio receiver. In return, the BBC guaranteed that it would operate independently but accountably, according to accepted rules, to provide a public service to inform, educate, and entertain.

The Commercial Radio Model

In the United States, radio broadcasting was locally organized from the start and soon evolved into a funding model based on on-air advertising and program sponsorship. Stations could affiliate with national networks, which aggregated audiences around the country by syndicating high-profile programs to attract higher value advertising. In one form or another, the commercial model has spread widely, associated particularly with the deregulation of public monopolies and the growth in music radio formats, which gathered pace through the second half of the 20th century. With deregulation has come consolidation of ownership within territories and transnationally, a trend in tension with the idea, strongly rooted in the United States as it is elsewhere, that radio's strength is as a focal point for a local community, serving local news and local advertising.

On the fringes of this category are for-profit stations operating outside of a nation's licensing system. Historically, this has included rebel stations using powerful MW transmitters to broadcast into a country from beyond the reach of their jurisdiction and local, commercially funded pirate stations operating illegally on FM in urban centers. In the era of the Internet, it includes the multitude of online stations working to develop a profitable business model in this unregulated environment in which barriers to entry are relatively low and no license to broadcast is required.

State-Financed External Services

Recognizing radio's power to influence, especially in the absence of television, governments of various ideologies were quick to fund international radio services as a branch of their foreign policy. Several phases and purposes of these external services can be identified, which align with the geopolitics of the age. During the 1930s, European colonial powers, notably the Netherlands, France, and Great Britain, created the infrastructures to broadcast radio direct to their dependent territories, both in their “home” language and, in an extension of their colonial missions, in the dominant indigenous languages of the region. During World War II, external services became overt and enormously important weapons of propaganda, and throughout the Cold War, radio remained pivotal in foreign policies for influencing the hearts and minds across that divide. After 1989, external services such as Voice of America, Radio China International, and the BBC World Service have continued with their multilingual broadcasts, via combinations of SW, satellite link, local relay, and opt-in and Internet services, although today the output is usually directed toward projecting cultural values as well as toward promoting trade relationships and national status. An optimistic view might see today's external services as manifestations of the motto the BBC adopted in 1927, “Nation Shall Speak Peace Unto Nation.”

Third-Sector Radio

This is a broad category, the shape of which varies according to the prevailing licensing regime, but stations in this category have two things in common: They represent an alternative to the established radio available in their region, and they are not-for-profit, reliant on alternative sources of low-level funding and the enthusiasm of volunteers. The category encompasses grassroots listener-sponsored radio, which began in the United States as early as 1949; volunteer-supported community radio; student and hospital radio; grant-funded development and educational radio projects, such as those run by UNESCO; as well as underground or liberation radio working counter to the propaganda of state-run media in an authoritarian regime. After the civil rights and countercultural upheavals of the mid- to late 1960s, demand for alternatives to mainstream broadcasting emerged as part of the wider movement by or for minority social groups to claim political identity and influence. Such communities have typically been defined geographically, as in the case of a rural mining community or a minority ethnic or economically deprived inner-city population. For many such audiences, an FM or AM license remains the most accessible, despite the Internet offering the flexibility of reaching locally or nationally or globally dispersed “communities of interest.”

Trends in the Regulation of Radio

Around the world radio is regulated through systems for licensing access to the finite resource of the internationally accepted radio frequencies: The awarding of a license by the relevant agency is first based on a judgment of who is a fit and proper person to run a station, but ultimately the sanction for breaking the terms of the license is that it can be withdrawn. For this reason, governments have found it easier to create regulations specific to radio (and subsequently television) than for print media. The two main pillars of regulation specific to radio are (a) maintaining a choice of listening and therefore competition between stations and (b) defining what, in terms of content, constitutes a public service. The former derives from the commercial model, relying on market forces to determine acceptable content, and the latter comes from the publicly funded model, where competition is absent. Both pillars are represented to varying degrees in every nation's licensing regime, but a clear emphasis toward one or the other can usually be discerned.

The process of digitalization of mass media effectively nullifies management of limited resource as providing the basis on which regulation of broadcasting is constructed. Almost all nations are now experiencing an explosion of choice of media and mass entertainment services, at least for their wealthier citizens. In the 21st century, the effect has been to increase pressure for deregulation on the basis that radio stations must be allowed to compete effectively to survive, with as few restrictions as possible. Internet-only radio stations are subject to the laws of the country in which they are based insofar as they are enforceable in practice, but otherwise they are entirely independent from regulation.

Global and Cultural Effects of Radio

The uses of radio are often discussed and theorized in terms of the overlapping categories of information, education, and entertainment. As the first of the electronic mass media, its effect can be summarized as having accelerated and amplified cultural change, which was an effect advanced by television and now the Internet. Radio's identity and importance within the media mix do not seem to have diminished since radio listening is either stable in the developed markets or increasing in developing and recently deregulated markets.

In information-poor regions, radio plays a proportionally greater role than in media-saturated environments. Its importance here as a vital carrier of information is heightened on several levels: In rural areas, radio may remain the only accessible mass medium because receivers and batteries are relatively affordable and it is not dependent on public electricity; radio speaks to people in their own first or second language despite whether they can read; and in countries where many different languages are spoken and literacy rates are low, radio provides a culturally unifying force. In these kinds of environments, radio has been recognized as having measurable democratizing effects—an exact mirroring of the early idealistic aspirations that greeted its arrival in the West.

In 2010, estimates of the number of licensed radio stations around the world vary around the 50,000 mark. The near-infinite capacity for online-only radio streams and on-demand services already adds thousands more, with most of them being 100% reliant on playing recorded music in genre-specific streams. The output of the greatest proportion of the licensed radio stations also falls into this entertainment category, using playlisted popular music as the vehicle for targeting their audience, supplemented with varying proportions of news and “broadcast talk” crafted to sound spontaneous, culturally specific, and conversational.

Critiques of music radio in the global context range between two extremes. One cites, as an example of music radio's role in lowering cultural barriers and building a cultural commons, the crucial role that crossover stations in the United States played in popularizing Black artists in the 1960s and to the formation of the cultural environments in which the civil rights movement could gain traction and spread worldwide. The contradictory view is that, whether coordinated or not, the relentless global dissemination of Anglo-American popular music represents a destructive cultural imperialism, which impoverishes local cultures by obliterating their traditions. The uniform model of formatted radio purveyed by transnational media interests is cited as a powerful agent in that process.

Other areas of radio entertainment that are particularly credited with influencing national cultural norms include satirical comedy; radio drama, especially in the episodic form of soap opera; and coverage of major sports.

Radio as entertainment is typically used as a secondary service, chosen while listeners are doing something else besides, and supplementary to, their consumption of a wider media diet on television, in print, or online. At critical moments, however, the entertainment function is relegated to give priority to public information. Radio's capabilities as an instantaneous and widely trusted source of news means it is often the quickest way to get information and official advice to more people within a given transmission area: information about, for example, a local transport crisis, emergency school closures, or a major national catastrophe.

Apart from news, other speech radio formats that carry current affairs and broadly educative content are magazine programs, documentaries, features, extended interviews, studio discussions, and phoneins. They are mainly found on publicly funded or third-sector stations. Where regulation permits, the phone-in has become extended with the addition, typically, of controversialist presenters into the commercial talk radio format. Critiques of talk radio identify its propensity to amplify reactionary political agendas and encourage divisive hate speak directed at “other” cultural groups.

However, the trend worldwide is toward deregulating the gatekeeping of who is allowed to broadcast, indicating that governments have become less concerned about radio's singular powers within today's information society: The earlier requirement that radio's radical potential be suppressed through regulation has been superseded by the hegemonic effects of audience segmentation, information overload, and the mass market in media as entertainment.

Some observers assume that radio must become irrelevant in a predominantly visual multimedia world; others point to its proven agility and growing international audience as indicators that it is well suited for a platform-agnostic future.

See also:

British Broadcasting Corporation (BBC), Cultural Commons, Internet, Media, Global, Music, News, Telegraph, Telegram, Telephone, Television, United Nations Educational, Scientific and Cultural Organization (UNESCO)

Further Readings
  • Briggs, A.Burke, P.(2002) A social history of the media: From Gutenberg to the Internet. Cambridge, UK: Polity Press.
  • Chignell, H.(2009) Key concepts in radio studies. London: Sage.
  • Hendy, D.(2000) Radio in the global age. Cambridge, UK: Polity Press.
  • Hilliard, R. L.Keith, M. C.(1996) Global broadcasting systems. Oxford, UK: Focal Press.
  • Hilmes, M., &Loviglio, J. (Eds.).(2002) Radio reader: Essays in the cultural history of radio. New York: Routledge.
  • Scannell, P. (Ed.). (1991) Broadcast talk. London: Sage.
  • Winston, B.(1998) Wireless and radio. In Winston, B. (Ed.), Media technology & society: A history—from the printing press to the superhighway. London: Routledge.
  • Priestman, Christopher
    Copyright © 2012 by SAGE Publications, Inc.

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