American Public Media
The United States government directly produces two radio services for direct public consumption: WWV (a time signal service on shortwave) and NOAA Weather Radio (a weather radio and emergency information network). Both services are almost entirely automated and use synthesized voice recordings. Unlike most other English-language countries, the United States does not have a federal government-owned national broadcaster, and the country's international government-operated broadcasters overseen by the Broadcasting Board of Governors (the most widely known being Voice of America) were expressly forbidden from being marketed to American citizens until 2013 and still neither owns nor affiliates with any AM or FM station. In lieu of a national broadcaster, the United States government instead subsidizes nonprofit radio stations 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 universities and public authorities for educational purposes and are financed by public and/or private funds, 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.) The BBC World Service has been distributed in the United States since 1986; until July 2012 by PRI, and since then by APM. It is also possible to listen to the World Service on shortwave.
The United States government has the direct authority to assume control over all radio stations in the United States at any time by way of the Emergency Alert System. All radio stations are required to have EAS equipment installed and operational in the event such a takeover is implemented. However, in practice (as evidenced when the EAS attempted its first ever national test on November 9, 2011), the EAS as currently configured is not entirely effective and produces poor audio quality. Other than the 2011 test, the EAS has never been used on a national scale.
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 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, primarily due to 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; the recording industry also sees Internet radio as a threat and has attempted to impose high royalty rates for the use of recorded music to discourage independent stations from playing popular songs.
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.
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