Radio in the United States
Radio broadcasting in the United States is a major mass medium. Unlike radio in most other countries, American radio has historically relied primarily on commercial advertising sponsorship on for-profit stations. The U.S. does not have a national broadcaster that aims its programs at the general public. Nonprofit broadcasting typically comes in three forms: radio evangelism, community radio, and government-subsidized public radio, all of which rely at least to some extent on listener donations. Shortwave broadcasting in the United States includes federal government programs, as well as a limited number of privately managed broadcasts, for overseas audiences. Radio broadcasting became popular in the 1920s, alongside the new film industry. The arrival of television in the 1950s forced radio into a niche role, as leading participants moved into the much larger field of television. In the 21st century, radio has been adjusting to the arrival of the Internet and Internet radio.
In 1912, most amateur-radio transmissions were restricted to wavelengths below 200 meters (i.e., frequencies above 1500 kHz) to prevent interference to future commercial broadcasters. The beginning of regular, commercially licensed radio broadcasting in the United States in 1920, along with the concurrent development of sound and color film in that decade, ended the print monopoly of mass media and opened the doors to the immediate (and pervasive) electronic media. By 1928, the United States had three national radio networks: two owned by NBC (the National Broadcasting Company), and one by CBS (the Columbia Broadcasting System). Until 1943, there were four major national radio networks: two owned by NBC, one owned by CBS and one owned by Mutual Broadcasting System. Stations were connected by broadcast-quality, leased telephone lines. NBC's second network became ABC, the American Broadcasting Company.
By 1919, after the war, radio pioneers across the country resumed transmissions. The early stations gained new call signs. Some early stations were started by newspapers: the first to do this was 8MK (today WWJ) in Detroit, which was owned by the Detroit News.  While many sources cite KDKA in Pittsburgh as the first station, and give its first broadcast as November 2, 1920, the question of who came first is still in dispute among historians.  For example, there is evidence 8MK was on the air with Michigan state election returns on August 31, 1920  Many other early stations were owned by small companies, such as AMRAD (the American Radio and Research Company, Medford Hillside MA); by some accounts, it broadcast voice and music as early as March 1916 , and was on the air sporadically till it began a daily schedule in May 1921, using call letters 1XE and later, WGI.  Perhaps the best-known early station began as experimental station 8XK, which became KDKA in 1920. AM radio signals traveled long distances, and KDKA's signal covered much of the country. The existence of early experimental radio stations encouraged young men (and a small number of young women) to build crystal sets (with ear phones) to listen to the new technical marvel. Entrepreneurs set up stations primarily with the goal of selling expensive console radio sets that the whole family could listen to, or which restaurants and shops would buy to attract customers.
Until early 1922, there were fewer than forty commercial stations broadcasting.  But in mid-1922, the so-called "radio craze" began, when several hundred new stations took to the airwaves, and thousands of people wanted to buy their own radio set. Even President Warren G. Harding had a radio installed in the White House. 
While "direct advertising" was not allowed in radio's formative years, per the order of then-head of the Department of Commerce Herbert Hoover , station owners wanted this policy changed, since it was very expensive to operate a radio station. By 1926, when the National Broadcasting Company went on the air, advertising was gradually allowed. Madison Avenue recognized the importance of radio as a new advertising medium. Advertising provided the major funding for most stations. The United States never had a license fee for set users.
The National Broadcasting Company began regular broadcasting in 1926, with telephone links between New York and other Eastern cities. NBC became the dominant radio network, splitting into Red and Blue Networks. The Columbia Broadcasting System (CBS) began in 1927 owned and directed by William S. Paley.
Prior to 1927, U.S. radio was supervised by the Department of Commerce. Then, the Radio Act of 1927 created the Federal Radio Commission (FRC). One of the FRC's early major moves was the implementation of General Order 40, designating AM radio stations as Clear Channel, Regional, and Local. Most stations' frequencies were changed to implement General Order 40 at 3:00 am EST on November 11, 1928.
Battle with the newspapersEdit
In the early 1930s, a furious battle broke out as the newspaper industry tried to block the transmission of news by radio. Advertising revenues were plunging during the Great Depression, and newspapers were desperate to protect their main flow of income from the upstart's threat to the status quo. In one particular incident, the newspapers attempted to claim that a broadcast of the H. G. Wells story The War of the Worlds caused a mass hysteria among listeners who thought the broadcast was real news, a myth that continues to the present day. Hollywood briefly became involved, by preventing its stars from appearing on the radio; it soon realized, however, that radio was not a direct competition and the greater visibility for their stars met even larger audiences. The newspaper attack failed, and the networks set up their own newsgathering and reporting system, which played a major role during World War II.
An FCC decision in 1939 required NBC to divest itself of its Blue Network. That decision was sustained by the Supreme Court in a 1943 decision, National Broadcasting Co. v. United States, which established the framework that the "scarcity" of radio-frequency meant that broadcasting was subject to greater regulation than other media. This Blue Network network became the American Broadcasting Company (ABC). Around 1946, ABC, NBC, and CBS began regular television broadcasts. The small DuMont Television Network, was founded earlier; it disbanded in 1956. In 1934, several independent stations formed the Mutual Broadcasting System to exchange syndicated programming, including The Lone Ranger and Amos 'n' Andy.
Advertising as the basis of profitabilityEdit
Paley at CBS was the first to fully realize that profitability depended primarily on maximizing the sales of commercials, which in turn meant reaching as large an upscale audience as possible. Surveys and polls could be used to determine not only the size of the audience, but their affluence. Frank Stanton, the president of CBS, worked with Columbia University sociologist Paul Lazarsfeld to develop techniques for measuring audiences.
Before Paley, owners typically viewed their stations as stand-alone outlets or as the broadcast equivalent of local newspapers. It was their job to sell ads to local business. Individual stations bought programming from the network and, thus, were considered the network's clients. Paley changed the business model by looking at national advertisers as the critical element. CBS therefore provided network programming to affiliate stations at a nominal cost, thereby ensuring the widest possible distribution for both the programming and the advertising. The advertisers then became the network's primary clients and, because of the wider distribution brought by the growing network, Paley was able to charge more for the ad time. Affiliates were required to carry programming offered by the network for part of the broadcast day, receiving a portion of the network's fees from advertising revenue. At other times in the broadcast day, affiliates were free to offer local programming and sell advertising time locally.
Growing importance of newsEdit
By 1940, the greatest audience attention was on the networks' evening programs of variety shows, music, and comedy and drama. In the morning and afternoon, smaller audiences (chiefly housewives) listened to 61 soap operas. Phone-in talk shows were rare, but disk jockeys attracted a following through their chatter between records. The most popular radio shows during the Golden Age of Radio. The Jack Benny Program, Fibber McGee and Molly, The Goldbergs and other top-rated American radio shows were heard by 30–35 percent of the radio audience.
In a major technical move, the FCC mandated that 795 of the 883 United States broadcasters on the AM band shift their broadcast frequencies on March 29, 1941, in what was called "Radio Movin' Day" in the press, and was the implementation of the North American Regional Broadcasting Agreement. The goal was to improve AM reception inside the United States, and reduce interference to and from stations outside the United States.
President Franklin Roosevelt's opponents had control of most newspapers in the 1930s; press reports were under their control and involved hostile editorial commentary. Roosevelt's solution was a series of 30 evening broadcasts in an informal, almost casual setting, dubbed "Fireside chats." Historian Douglas B. Craig says that he, "offered voters a chance to receive information unadulterated by newspaper proprietors' bias" through the new medium of radio."
Roosevelt's radio audiences averaged 18 percent during peacetime, and 58 percent during the war. His address of May 27, 1941, was heard by 70 percent of the radio audience.
Local radio in the Golden AgeEdit
All broadcast stations are licensed locally, in the past with mandated obligations to their "city of service," fulfillment of which for license renewal is today largely passé. For many a "250-watt station in my hometown," expensive facilities emulated the networks' in the form of multiple, acoustically fine studios in art deco style for local origination of music and variety programs, featuring local, mostly volunteer, talented teens and energetic young adults motivated by the possibility of being discovered. Local programs were "sustaining" (covered by general ad revenue), or the talent found their own sponsors and bought station time. Often paid just over minimum wage, "combo operator-announcers," later called DJs, nevertheless came to consider themselves entertainers, often in fact becoming local celebrities, who cultivated "on-air personalities," sometimes pairing one who was straight-laced with one playing the clown. Practical jokes by full-time staff were common, the unseeing audience none the wiser unless someone broke up laughing.
Continuous station operations were manual (until automation debuted in the 1970s), and could originate programming only three ways: live; live via remote telephone line (including network feeds as well as store openings and church services around town); or played from "electrical transcription" (ET) phonograph discs. ETs up to 16in diameter played 15 minute syndicated programs, mailed to stations by the thousands, many for government sales of savings bonds and military recruiting. Magnetic tape arrived after 1947 and the Bing Crosby/Ampex alliance. All sound was monophonic until introduction of the stereo LP in 1958, when sister stations "simulcast" the left signal on AM, the right on FM, requiring audiofans to set up two receivers. For both practitioners and attentive listeners, local radio during the Golden Age was fun.
Radio in education began as early as April 1922, when Medford Hillside's WGI Radio broadcast the first of an ongoing series of educational lectures from Tufts College professors. These lectures were described by the press as a sort of "wireless college." Soon, other colleges across the U.S. began adding radio broadcasting courses to their curricula; some, like the University of Iowa, even provided what today would be known as distance-learning credits. Curry College in Massachusetts introduced one of the nation's first broadcasting majors in 1932 when the college teamed up with WLOE in Boston to have students broadcast programs. In the 1950s, television courses became popular. After 2000, Internet-based transmission of college courses came on line. 2012 was the "year of the MOOC" (massive open online course).
After 1955 television's visual images replaced the audio-only limitation of radio as the predominant entertainment and news vehicle. Radio adapted by replacing entertainment programs with schedules of music interspersed with news and features, a free-form format adopted by NBC when it launched its popular weekend-long Monitor in 1955. During the 1950s automobile manufacturers began offering car radios as standard accessories, and radio received a boost as Americans listened to their car radios as they drove to and from work. Although this period saw the overall decline of the AM radio, some new stations, like the WGIV station in Charlotte dedicated to African American Music, were still coming up.
In the 1950s, as a result of television's increased popularity coupled with dramatically loosened restrictions on playing recorded music on air, the network model of radio dramatically declined. In its place was the first music radio format: top 40, the forerunner to modern contemporary hit radio. Top 40 stations could be operated locally and gave rise to the disc jockeys, who became prominent local celebrities in their own right. Top 40 became the outlet for the relatively new style of music known as rock and roll.
FM radio, which was the successor to the failed Apex band (also known as ultra-shortwave) experiments of the 1930s, arrived in the United States in 1941, but it was not until the 1960s that it saw broad adoption. This was due in large part to a 1945 Federal Communication Commission decision which shifted FM's allocation of frequencies from 42-50 MHZ to 88-108 MHz. This allowed FM much more room for growth when listeners arrived after 1960, but rendered hundreds of thousands of already-existing Armstrong-FM sets useless overnight, and set adoption of FM in the United States back years. The FCC later decided to reduce program duplication on AM and FM sister stations, giving the younger medium space to grow. The better sound fidelity of FM, the less static, dated a natural for musical programming. The first FM stations were primarily instrumental, featuring formats that would come to be known as easy listening and beautiful music, and were targeted at shopping centers. Other, later FM sign-ons became known for experimentation; the early freeform stations eventually evolved into progressive rock, the first radio format designed specifically to showcase rock music. From progressive rock came album-oriented rock, which in turn spawned the modern formats of classic rock, active rock and adult album alternative.
Top 40 radio would begin arriving on the FM band in the 1970s as FM reached critical mass. As the amount of archival music from the rock and roll era began to expand, oldies radio stations began to appear, later evolving into the modern classic hits and later adult hits formats. FM radio made a major expansion in the late 1980s with the FCC's Docket 80-90, which expanded the number of available FM licenses in the suburban areas of the United States. Country music in particular, previously only heard on rural AM stations particularly in the Southern and Western United States, benefited from this docket, moving en masse to FM; the beautiful music and easy listening formats mostly died out, with adult contemporary music taking its place.
Meanwhile, the AM band began declining. All-news radio became popular in the major cities in the late 1960s. As each successive radio format moved to FM, AM radio stations were left with fewer and fewer options. One of the last "AM only" formats was MOR, or "middle-of-the-road", the direct forerunner of adult contemporary music and adult standards. Talk radio, although it had a small following in the cities, did not achieve mainstream popularity until the 1980s, when a combination of factors led to the rise of conservative talk radio. The politically charged format swept the country, bringing stardom to one of its pioneers, Rush Limbaugh. Also rising to popularity in the late 1980s was sports radio, which was dedicated to talk about sports as well as the broadcasting of sports events. What few country stations remained on AM typically shifted to classic country and focused primarily on older music.
While shock jocks had been in existence since at least the 1970s (see, for example, Don Imus) and the morning zoo radio format was popular among local stations beginning in the 1980s, the first shock jock to make a major national impact was Howard Stern, whose New York-based show was syndicated nationwide beginning in the early 1990s. Stern built a multimedia empire that incorporated television, books and feature films, which led to him bestowing upon himself the title of "King of All Media." Stern left terrestrial radio in 2005.
Satellite networks began replacing landline-based models in the 1980s, making possible wider and quicker national distribution of both talk and music radio. At the same time, the traditional networks started collapsing: NBC Radio and Mutual both were acquired by syndication company Westwood One, while ABC (both radio and television) was acquired by Capital Cities Communications. CBS would later acquire Westwood One, only to spin it off in 2007; as of 2015, Westwood One is now in the hands of Cumulus Media. ABC would end up in the hands of The Walt Disney Company, who broke the radio network up in 2007; Disney owns portions of the old network, while the rest of it is in the hands of Cumulus. Mutual was dissolved in 1999, replaced by CNN Radio, which itself was dissolved in 2012. CBS still owns much of its original network, the last of the four major networks of the Golden Age to do so; its programming is mostly funneled through Cumulus.
Two other major commercial networks have appeared since the 1990s: Premiere Networks, the division of iHeartMedia, and the Salem Radio Network. Premiere owns the radio distribution rights to the current "fourth major network", Fox (which owns no radio stations), and distributes that company's news and sports radio broadcasts. iHeart's immediate predecessor, Clear Channel Communications, benefited from the Telecommunications Act of 1996, which allowed for greater media consolidation, and built a large empire of both large and small market radio stations; Clear Channel, having overextended itself, jettisoned most of its small-market stations (as well as its now-dissolved television division) in the late 2000s. The Salem Radio Network, a division of Salem Communications (which outside of radio also has a large Internet operation), primarily has a Christian/conservative focus and specializes in Christian music, preaching stations and conservative talk radio, both owning stations and producing original content. Oaktree Capital Management briefly attempted a foray into building a radio network when it purchased the assets of several struggling radio networks in the late 2000s; while it still owns stations through its Townsquare Media holding company, it has since spun off its network holdings (which operated under the Dial Global brand) to Cumulus.
Direct-to-consumer subscription satellite radio began appearing in the United States in the early 2000s, but despite heavy investment in programming has continually lost money and has less than a tenth of the reach of terrestrial radio. The two competing satellite radio services, Sirius and XM, merged to form Sirius XM Radio in 2009 and now has a government-regulated monopoly on the format.
Broadcast call signsEdit
While broadcast radio stations will often brand themselves with plain-text names, identities such as "cool FM", "rock 105" or "the ABC network" are not unique. Another station, in another city or country, may (and often will) have a similar brand; the name of a broadcast station for legal purposes is, therefore, normally its ITU call sign.
Broadcast stations in North America generally use call letters in the international series, with common conventions followed in each country. In the United States, the first letter generally is K for stations west of the Mississippi River and W for those east of the Mississippi; all new call signs have had four characters since 1930, although there are historical three-character calls still in use (such as WOR in New York City, WBZ in Boston, WOL in Washington DC, WSB in Atlanta, WMC in Memphis, WGN in Chicago, KOA in Denver, KSL in Salt Lake City, KEX in Portland, Oregon, KUT in Austin, and KFI in Los Angeles).
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The expansion and dominance of FM radio, which has better audio quality but a more-limited broadcast range than AM, represented the major technical change in radio during the 1970s and 1980s. FM radio (aided by the development of smaller portable radios and "Walkman" headsets) dominates music programming, while AM has largely shifted to talk and news formats. Talk radio became more popular during the 1980s as a result of improved satellite communications, the repeal of the Fairness Doctrine and (by the mid-1990s) extensive concentration of media ownership stemming from the Telecommunications Act of 1996. While before the 1980s talk radio was primarily a local phenomenon, the development of national spoken-word programming contributed to the renewed popularity of AM radio. However, this popularity is fading as previously AM-only stations begin moving their operations to FM simulcasts or translators, and as the audience of talk radio ages.
Both FM and AM radio have become increasingly specialized. Music formats (for instance) comprise a variety of specializations, the top five in 1991 being "country and western", "adult contemporary", "Top 40", "religion" and "oldies". Radio has been shaped by demographics, although to a lesser degree than television; modern radio formats target groups of people by age, gender, urban (or rural) setting and race. As such, freeform stations with broad-spanning playlists have become uncommon on commercial radio.
In an era in which TV is the predominant medium, the reach of radio is still extensive. Ninety-nine percent of American households in 1999 had at least one radio; the average is five per household. Every day, radio reaches 80 percent of the U.S. population. Revenue more than doubled in a decade, from $8.4 billion in 1990 to more than $17 billion in 2000. Radio continues to prevail in automobiles and offices, where attention can be kept on the road (or the task at hand) while radio is an audio background. The popularity of car radios has led to drive time being the most listened-to dayparts on most radio stations, followed by midday (or the "at work" shift). Transistor radios, a technology that has been available since the 1950s, were the method of choice for listening to music on the go for most of the late 20th century, before digital media players and later smartphones (many of which have FM radios as part of their hardware) took those roles in the 20th century.
The majority of programming in the United States is in English, with Spanish the second-most popular broadcast language; these are the only two languages with domestically produced, national radio networks. In the largest urban areas of the United States, "world ethnic" stations may be found with a wide variety of languages (including Russian, Chinese, Korean and the languages of India); relatively widespread languages French and German have comparatively few radio outlets (in the case of German, due to the fact that most of its speakers are Amish or from similar sects and thus shun radio technology). French speakers can generally receive programming direct from Canadian broadcasters, which are receivable across the Canada–US border and a handful of local stations serving the Haitian diaspora and Creole populations also serve areas in the southeast.
Until the 1980s, most commercial radio stations were affiliated with large networks such as ABC, CBS, the Mutual Broadcasting System, NBC, and others (e.g., RKO in the 1980s). The traditional major networks that had dominated the history of American radio up to that point began to be dissolved in the 1980s; RKO was forced to break up in a billing scandal, while NBC Radio and Mutual sold their assets to up-and-coming syndicator Westwood One, which itself would be bought by rival CBS in the 1990s. ABC maintained most of its radio network until 2007, when it sold off most of its stations to Citadel Broadcasting and later Cumulus Media (it maintains two specialty networks, sports-oriented ESPN Radio and youth top 40 Radio Disney, the latter of which has largely shifted to Internet radio; ABC still produces radio programming in addition to its terrestrial networks). CBS sold off Westwood One to private equity interests in the late 2000s as well, but unlike its rivals maintained ownership of its flagship stations. As of 2012, most commercial radio stations are controlled by media conglomerates and private equity firms such as Bain Capital (Clear Channel Communications), Oaktree Capital Management (Townsquare Media) and Cumulus Media.
Unlike most countries, the national and state governments in the U.S. do not operate any stations or networks directed at its own domestic citizens. It does operate networks overseas through the Broadcasting Board of Governors; the most widely known of these networks is Voice of America, which serves a general worldwide audience; other networks target specific geographic regions. Broadcasting Board of Governors networks were, until 2013, expressly forbidden from being marketed to American citizens; they still neither own nor affiliate with any AM or FM station. The U.S. also provides the American Forces Network, a service for American armed servicemen stationed overseas that mostly relays commercial programming; AFN broadcasts are restricted to listeners in Japan, Korea and parts of Europe. In lieu of a national broadcaster, the United States government instead subsidizes nonprofit radio programming through the Corporation for Public Broadcasting.
In 1998, the number of U.S. commercial radio stations had grown to 4,793 AM stations and 5,662 FM stations. In addition, there are 1,460 public radio stations. Most of these stations are run by private foundations, universities and public authorities for educational purposes and are financed by donations, foundations, subscriptions and corporate underwriting. Much public-radio broadcasting is supplied by NPR (formerly National Public Radio). NPR was incorporated in February 1970 under the Public Broadcasting Act of 1967; its television counterpart, PBS, was also created by the same legislation. (NPR and PBS are operated separately from each other.)
A new form of radio which is gaining popularity is satellite radio. Sirius XM Radio has a monopoly on the technology after the merger of Sirius Satellite Radio and XM Satellite Radio. Unlike terrestrial-radio broadcasting, most channels feature few (or no) commercials. Satellite-radio content is not regulated by the Federal Communications Commission (FCC).
Cable radio, a slightly older technology, has also become widespread; Music Choice is the market leader in this field, with its primary competitors being Sirius XM, Muzak, DMX, Sonic Tap and Canada-based Galaxie. CRN Digital Talk Radio Networks specialize in talk radio. Cable radio has the disadvantage that it requires a cable TV hookup, limiting its use outside the home.
Unlike the mandated digital television transition, the U.S. government has not mandated a transition to digital radio, although it allows digital radio to be broadcast. The national standard is HD Radio, a proprietary in-band on-channel format that allows digital and analog signals to be broadcast simultaneously. Radio companies aggressively marketed HD Radio throughout the 2000s, touting its clearer signal and capacity for digital subchannels, but the technology never caught on with the general public. The negatives were cost, signal reception problems, a general lack of quality programming on the subchannels, and (especially on AM HD stations) adjacent-channel interference. HD Radio's primary use has been to exploit an FCC loophole to allow low-power broadcast translators to carry HD subchannels in analog, thus giving radio station groups the ability to program more program services in a market than the federally mandated maximum number of stations allowed. FMeXtra is another subchannel service authorized for use in the United States, although that service is generally limited to voice transmissions due to lower bandwidth.
Internet radio, digital music players and streaming-capable smartphones are a challenge to terrestrial radio. Unlike satellite radio, most Internet stations do not require a subscription; several of the more popular ones use algorithms which allow listeners to customize the music they want to hear and select new music which may interest them. The proliferation of internet-based stations (which are more numerous and easier to set up than their television counterparts) creates a threat of audience fracturing beyond that experienced by television due to cable and satellite providers.
Although not nearly to the extent that AM radio has declined in neighboring Canada, AM radio has also begun to decline in the United States. To partially combat this, radio ownership groups have increasingly moved their signals to FM, either through low-power broadcast translators (primarily on small, independent and/or rural stations) or through simulcast on full-market FM stations. The AM-to-FM phenomenon began primarily in mid-sized markets, where there is more bandwidth and less competition, but has since progressed even to New York City, where as of 2012 sports-talk AM stations WEPN and WFAN have both acquired FM stations with the intent to either move or simulcast their AM programming. By 2013 most of the AM/FM simulcasts had been discontinued, in part due to redundancy and the fact that most listeners to AM stations stayed with AM while very few new listeners were picked up on the FM side.
- Call signs in North America
- List of 50 kW AM radio stations in the United States
- List of United States radio networks
- Amateur radio
- Crossley ratings, polling to rate size & composition
- Internet radio, online streaming
- Radio News Magazine for Amateur radio fans
- War Emergency Radio Service, WWII
- List of AM-band radio station lists issued by the United States government
Public Radio NetworksEdit
Abridged from U.S. State Department IIP publications and other U.S. government materials.
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