terrestrial radio traditional broadcast radio, which involves signals that are broadcast from transmission towers on the ground and picked up by radio sets
cable radio a service in which cable firms send music to customers through their wires
satellite radio radio broadcast by transmitting signals to satellites that retransmit them to radio sets
internet radio a service in which streaming audio is distributed to digital devices that access the Web location
Just as radio executives in the 1940s had feared, the popularity of the many new FV stations scattered audiences across more channels and made it harder for stations to draw advertisers. From the 1970s onward—and especially during the 1980s anc 1990s—radio executives found that they had to position their stations toward very particular types of people with very particular lifestyles and listening tastes to attract sponsors. Industry consultants helped station executives relate particular social categories (age, race, gender, ethnicity) to particular formats (album-oriented rock, Top 40, middle of the road, country, and multiple variations of these) to signal to people scanning the airwaves whether or not a station was for them.
AM stations struggled to find niches for themselves in the new radio world. Many had a hard time staying afloat, and some even went out of business. The ones that remained tended to focus on nonmusic programming (all talk, all news, all business/ financial, all sports), religious, and ethnic (often Spanish-language) formats. In the 1990s, talk stations hit a sort of a jackpot. The popularity of such on-air characters as Rush Limbaugh, G. Gordon Liddy, Laura Schlessinger, and Oliver North drew millions to those stations and boosted advertising sales.
Radio executives also redefined the idea of a network. The traditional notion of a network as a distributor of all sorts of programming to affiliates had faded with the rise of television. In its place emerged organizations that delivered material tailored to the new demands of segmented, targeted radio. The ABC radio network set the pattern for this approach in 1968, when it reorganized into four services—contemporary, informational, entertainment, and FM. It offered hourly news reports styled to mirror different formats. As the delivery of programming by satellite became possible in the 1970s, more and more network-like services arose to provide stations with everything from around-the-clock music formats to special music concerts that matched their formats. Cable television firms even began to offer their customers audio music services that could not be received over the air.
To distinguish themselves from services provided by new delivery technologies, executives in the traditional radio industry began to refer to their business as terrestrial radio. Terrestrial radio involves signals that are broadcast from transmission towers on the ground and picked up by radio sets. That is different from cable radio, where cable firms send music to customers through their wires, from satellite radio, which involves transmitting signals to satellites that retransmit them to radio sets, and from internet radio, where audio is distributed to digital devices that access the Web location. Apart from encouraging new networks, the fragmentation of terrestrial radio encouraged consolidation—the purchase of several radio stations in an area by one company. Before the late 1990s, the FCC did not allow broadcasters to own more than one FM and one AM station in a given area. However, the Telecommunications Act of 1996 did away with such restrictions, allowing broadcast companies to snatch up several AM and FM properties in the same market. That sparked the creation of large radio conglomerates, most notably Clear Channel Communications, which controlled large proportions of radio advertising in markets across the country.
The rise of the radio conglomerates has sparked the criticism that much of terrestrial radio is repetitive, not innovative, and clogged with commercials. This criticism is happening at a time when digital media such as satellite radio, internet-linked computers, iPods, MP3 players, mobile phones, and related technologies are opening up new ways for people to get audio programming that radio has long provided to them. Once again, radio executives stand between an old and new world. They have a lot invested in traditional broadcast radio, but their audiences are declining. So they are trying to understand how to adapt to, and compete with, the new technologies. Let's take a look at the established and emerging worlds of radio. We start with today's terrestrial radio world, then examine digital competition to the radio industry and the industry's response to it. As we will see, there certainly is a lot of music streaming out there.
TECH & INFRASTRUCTURE HOW THE RADIO SPECTRUM WORKS
All your life you have heard about “AM radio” and “FM radio,” “VHF” and “UHF” television, “citizens band radio” “short-wave radio,” and so on. Have you ever wondered what all of those different names really mean?
A radio wave is an electromagnetic wave that is propagated by an antenna. Radio waves have different frequencies, and by tuning a radio receiver to a specific frequency you can pick up a specific signal. In the United States, the FCC (Federal Communications Commission) decides who is allowed to use what frequencies for what purposes, and it issues licenses to stations for specific frequencies.
When you listen to a radio station and the announcer says, “You are listening to 91.5 FM WRKX The Rock!” what the announcer means is that you are listening to a radio station with the FCC-assigned call letters WRKX that is broadcasting an FM (frequency-modulated) radio signal at a frequency of 91.5megahertz (MHz). Megahertz means “millions of cycles per second,” so saying that the frequency is 91.5 MHz means that the transmitter at the radio station is oscillating at a frequency of 91,500,000 cycles per second. Your FM radio can tune in to that specific frequency and give you clear reception of that station. All FM radio stations transmit in a band of frequencies between 88 and 108 MHz. This band of the radio spectrum is used for no other purpose but FM radio broadcasts.
In the same way, AM radio is confined to a band from 535 to 1,700 kilohertz (kHz) (kilo means “thousands,” so this means from 535,000 to 1,700,000 cycles per second). So an AM radio station that says, “This is AM 680 WPTF!” means that the radio station has the
FCC-assigned call letters WPTF and is broadcasting an AM (amplitude-modulated) radio signal at 680 kHz. Common frequency bands include the following:
· AM radio: 535 kHz to 1.7 MHz
· Short-wave radio: bands from 5.9 to 26.1 MHz
· Citizens band (CB) radio: 26.96-27.41 MHz
· Television stations: 54-88 MHz for channels 2-6
· FM radio: 88-108 MHz
· Television stations: 174-220 MHz for channels 7-13
Why is AM radio in a band from 535 to 1,700 kHz whereas FM radio is in a band from 88 to 108 MHz? It is all completely arbitrary, and a lot of it has to do with history. For example, AM radio has been around a lot longer than FM radio. The first radio broadcasts occurred in 1906 or so, and frequency allocation for AM radio took place during the 1920s. (The predecessor to the FCC was established by Congress in 1927.)
In the 1920s, radio and electronic capabilities were fairly limited, hence the relatively low frequencies for AM radio. Television stations were pretty much nonexistent until 1946 or so, when the FCC allocated commercial broadcast bands for TV. By 1949, a million people owned TV sets, and by 1951 there were 10 million TVs in America. FM radio was invented by a man named Edwin Armstrong in order to make high-fidelity (and static-free) broadcast of music possible. He built the first station in 1939, but FM did not become really popular until the 1960s.
Source: Adapted with permission from http://www.howstuff- works. com/radio-spectrum.htm (accessed February 20, 2007)
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