Citizens band radio


Citizens band radio is a land mobile radio system, a system allowing short-distance one-to-many bidirectional voice communication among individuals, using two-way radios operating near 27 MHz in the high frequency or shortwave band. Citizens band is distinct from other personal radio service allocations such as FRS, GMRS, MURS, UHF CB and the Amateur Radio Service. In many countries, CB operation does not require a license and may be used for business or personal communications.
Like many other land mobile radio services, multiple radios in a local area share a single frequency channel, but only one can transmit at a time. The radio is normally in receive mode to receive transmissions of other radios on the channel; when users want to communicate they press a "push to talk" button on their radio, which turns on their transmitter. Users on a channel must take turns transmitting. In the US and Canada, and in the EU and the UK, transmitter power is limited to 4 watts when using AM and FM and 12 W PEP when using SSB. Illegal amplifiers to increase range are common.
CB radios using an omni-directional vertical antenna typically have a range of about depending on terrain, for line of sight communication; however, various radio propagation conditions may intermittently allow communication over much greater distances. Base stations however may be connected to a directional Yagi–Uda antenna commonly called a Beam or a Yagi.
Multiple countries have created similar radio services, with varying technical standards and requirements for licensing. While they may be known by other names, such as the General Radio Service in Canada, they often use similar frequencies and have similar uses, and similar technical standards. Although licenses may be required, eligibility is generally simple. Some countries also have personal radio services in the UHF band, such as the European PMR446 and the Australian UHF CB.

History

United States

Origins

The citizens band radio service originated in the United States as one of several personal radio services regulated by the Federal Communications Commission. These services began in 1945 to permit citizens a radio band for personal communication. In 1948, the original CB radios were designed for operation on the 460–470 MHz UHF band. There were two classes of CB radio: "A" and "B". Class B radios had simpler technical requirements, and were limited to a smaller frequency range. Al Gross established the Citizens Radio Corporation during the late 1940s to manufacture class B handhelds for the general public. Originally designed for use by the public sector, the Citizens Radio Corporation sold over 100,000 units, primarily to farmers and the US Coast Guard.
Ultra-high frequency radios, at the time, were neither practical nor affordable for the average consumer. On September 11, 1958 CB service class D was created on 27 MHz, and this band became what is commonly known today as "Citizens Band". Only 23 channels were available at the time; the first 22 were taken from the former amateur radio service 11-meter band, and channel 23 was shared with radio-controlled devices. Some hobbyists continue to use the designation "11 meters" to refer to the Citizens Band and adjoining frequencies. Part 95 of the Code of Federal Regulations regulates the class D CB service, on the 27 MHz band, since the 1970s and continuing today. Most of the 460–470 MHz band was reassigned for business and public-safety use; CB Class A is the forerunner of the General Mobile Radio Service. CB Class B is a more distant ancestor of the Family Radio Service. The Multi-Use Radio Service is another two-way radio service in the VHF high band. An unsuccessful petition was filed in 1973 to create a CB Class E service at 220 MHz, which was opposed by amateur radio organizations and others. There are several other classes of personal radio services for specialized purposes.
During the 1960s, the service was used by small businesses, truck drivers and radio hobbyists. By the late 1960s, advances in solid-state electronics allowed the weight, size, and cost of the radios to fall, giving the public access to a communications medium previously only available to specialists. CB clubs were formed; a CB slang language evolved alongside ten-code, similar to those used in emergency services.

1970s popularity

After the 1973 oil crisis, the U.S. government imposed a nationwide 55 mph speed limit, and fuel shortages and rationing were widespread. Drivers used CB radios to locate service stations with better supplies of fuel, to notify other drivers of speed traps, and to organize blockades and convoys in a 1974 strike protesting the new speed limit and other trucking regulations. The radios were crucial for independent truckers; many were paid by the mile, and the 55 mph speed limit lowered their productivity.
Their use spread further into the general population in the US in the middle of the 1970s. Originally, CB radios required the use of a callsign in addition to a purchased license. However, when the CB craze was at its peak, many people ignored the requirement and invented their own nicknames. Lax enforcement of the rules on authorized use of CB radio led to further widespread disregard of regulations. Individual licensing came to an end on April 28, 1983.
The growing popularity of CB radios in the 1970s was frequently depicted in film, television, music and books. Movies such as Smokey and the Bandit, Breaker! Breaker!, Handle with Care, and Convoy, made heavy reference to the phenomenon, as did television series such as Movin' On, The Dukes of Hazzard and the animated series CB Bears helped cement CB radio's status as a nationwide craze in the United States over the mid- to late-1970s. In Stephen King's 1978 novel The Stand, Ralph Brentner's radio signal from Boulder, Colorado was able to be received over CB. The phenomenon also inspired several country and rock music songs in 1975 and 1976.
  • C. W. McCall's novelty song "Convoy" climbed to #1 on the Billboard Hot 100 in January 1976 and to #2 on the UK singles chart during the spring of 1976. The song inspired the 1978 film of the same name directed by Sam Peckinpah. In the UK, BBC Radio One DJs Dave Lee Travis and Paul Burnett covered the song with altered lyrics, released as "Convoy GB" under the moniker Laurie Lingo & the Dipsticks. The cover peaked at #4 on the UK chart in the spring of 1976. McCall also recorded "'Round the World with the Rubber Duck", a sequel to "Convoy". It was released in the late spring of 1976 and peaked at #1 on the Billboard Bubbling Under Hot 100 chart.
  • Dave Dudley's 1975 novelty country song "Me and ol' CB" peaked at #12 on the Billboard Hot Country Songs chart and at #8 on the Canadian country chart.
  • "The White Knight", a novelty country music song, was written by Jay Huguely, who – recording as Cledus Maggard & The Citizen's Band – enjoyed a brief run of national popularity with the song when it became a hit in 1976, peaking at #19 on the Billboard Hot 100.
  • "One Piece At A Time" by Johnny Cash peaked at #12 on the UK charts in the early summer of 1976.
  • The lyrics to the Outlaws's country rock song "Breaker-Breaker" capitalize on the fad. The record peaked at #94 on the Billboard Hot 100 in the spring of 1976.
  • "Teddy Bear" by country singer Red Sovine charted at #6 in the UK in the late summer of 1976.
  • Country singer Rod Hart's "C.B. Savage" is a gay-themed country novelty song about truckers plagued by a mysterious effeminate CB aficionado.
Betty Ford, the former First Lady of the United States, used the CB handle "First Mama".
Voice actor Mel Blanc was also an active CB operator, often using "Bugs" or "Daffy" as his handle and talking on the air in the Los Angeles area in one of his many voice characters. He appeared in an interview in the NBC Knowledge television episode about CB radio in 1978. Similar to Internet chat rooms a quarter-century later, CB allowed people to get to know one another in a quasi-anonymous manner.
Originally, the U.S. had 23 CB channels; the 40 channel band plan was implemented in 1977. Two more channels between 22 & 23, commonly referred to as 22A & 22B, were available. Several people had 22A, but few had 22B. In the early 1970s Radio Shack sold a "base station" CB radio that contained a crystal for each of the 23 channels, two extra slots existed, and one could order the 22A & 22B crystals for an easy plug-in. Channel 9 was officially reserved for emergency use by the FCC in 1969. Channel 10 was originally often used for highway travel communications east of the Mississippi River, and channel 19 west of the Mississippi; channel 19 then became the preferred highway channel in most areas, as it did not have adjacent-channel interference problems with channel 9. Many CBers called channel 19 "the trucker's channel". The FCC originally restricted channel 11 for use as the calling channel.
The original FCC output power limitation for CB radios was "5 watts DC input to the final amplifier stage", which was a reference to the earlier radios equipped with tubes. With solid state radios becoming more common in the 1970s, the FCC revised this specification at the same time the authorized channels were increased to 40. The current specification is simply "4 watts output or 12 watts output " as measured at the antenna connector on the back of the radio. The old specification was often used in false advertising by some manufacturers who would claim their CB radios had "5 watts" long after the specification had changed to 4 watts output. The older 23 channel radios built under the old specifications typically had an output of around 3.5 to 3.8 watts output when measured at the antenna connector. The FCC simply rounded up the old "5 watts DC input to the final amplifier stage" specification to the new "4 watts output as measured at the antenna connector on the back of the radio", resulting in a far simpler and easier specification.
Initially, the FCC intended for CB to be the "poor man's business-band radio", and CB regulations were structured similarly to those regulating the business band radio service. Until 1975, only channels 9–14 and 23 could be used for "interstation" calls. Channels 1–8 and 15–22 were reserved for "intrastation" communications. After the inter-station/intra-station rule was dropped, channel 11 was reserved as a calling frequency ; however, this was withdrawn in 1977. During this early period, many CB radios had "inter-station" channels colored on their dials, while the other channels were clear or normally colored. It was common for a town to adopt an inter-station channel as its "home" channel. This helped prevent overcrowding on channel 11, enabling a CBer to monitor a town's home channel to contact another CBer from that town instead of a making a general call on channel 11.