citizens' band (CB) radio - Scope, CB Radio today, CB Usage in the United States, CB Usage Worldwide, CB Antennas

A short-range two-way radio communication system for use by members of the public, typically consisting of a transceiver (a combined transmitter-receiver) and aerial. CB originated in the USA in the 1940s, and is particularly associated with long-distance truck drivers, who evolved a special language of codes and jargon to keep their messages from being understood by the police and public, such as 10–1 ‘poor reception’, 10–4 ‘message understood’, smokey ‘policeman’. Many CB clubs were formed, especially in the 1970s. In the UK, the use of CB was illegal until 1981, when a special channel was authorized. The technology has now been largely replaced by cellular phones.

Citizens' Band radio (CB) is, in the United States, a system of short distance radio communication between individuals on a selection of 40 channels within the single 27 MHz (11 meter) band. The CB radio service should not be confused with FRS, GMRS, MURS or amateur radio. Similar personal radio services exist in other countries, with varying requirements for licensing and differing technical standards. In many countries, CB does not require a license and unlike amateur radio, it may be used for commercial communication.

Scope

The Citizens' Band radio service in the United States is one of several personal radio services regulated by the FCC. These services began in 1945 to permit citizens a short-distance radio band for personal communication (e.g.

At the time, the technology wasn't advanced enough to make a UHF radio practical for the average consumer. So, in 1958 the Class D CB service was opened at 27 MHz and this is what is popularly known as CB. Previously, this was a government band (primary allocation to US Forest service, military, etc.) with a secondary allocation for the amateur radio service.

Most of the 460-470 MHz band was reassigned for business and public safety uses, but Class A CB is the ancestor of the present General Mobile Radio Service GMRS. The Multi-Use Radio Service is another two-way radio service, in the VHF high band. An unsuccessful petition was made in 1973 to create a Class E CB service at 220 MHz, but this was opposed by amateur radio organizations and others. There are several other classes of personal radio services for specialized purposes such as remote control devices.

While parts of this article are specific to the United States, several countries have similar radio services.

On the other hand, some foreign personal radio services, such as the European PMR446 and the Australian UHF CB are more similar to the American FRS or GMRS services than the CB service, and so are not covered in this article. The prominent use of CB radios in mid- and late-1970s films (see list below), television shows such as The Dukes of Hazzard (debuted 1979), and in popular novelty songs such as C.W.

Originally CB did require a license and the use of a call sign but when the CB craze was at its peak, many people ignored this requirement and used made up nicknames or "handles". The use of handles instead of call signs is related to the common practice of using the radios to warn other drivers of speed traps during the time when the United States dropped the national speed limit to 55 mph (90 km/h) beginning in 1974 in response to the 1973 hike in oil prices. The many restrictions on the authorized use of CB radio led to widespread disregard of the regulations, most notably in antenna height, distance restriction for communications, licensing and the use of call signs, and allowable transmitter power.

Originally, there were only 23 CB channels in the U.S.; In the 1960s, channels 1-8 and 15-22 were reserved for "intrastation" communications among units under the same license, while the other channels (9-14 and 23) could be used for "interstation" calls to other licenses. Channel 10 was used for highway communications, and channel 11 was used as a general calling channel. Later, channel 19 became the preferred highway channel in most areas, as it did not have the adjacent-channel interference problems with channel 9.

Until the late 1970s when synthesized radios appeared, CB radios were controlled by plug-in quartz crystals.

In 1973, various groups petitioned the FCC for an allocation of frequencies near 220 MHz for a new "Class E" Citizen's Band service. While the "Class E" initiative was not successful early on, the Reagan Administration’s sponsored some of these requirements for the development of the Family Radio Service, General Mobile Radio Service and Multi-Use Radio Service.

Throughout the 1970s and early 1980s a phenomenon was developing over the CB radio.

In Britain, some people were using CB radio illegally in the 1970s, a craze which suddenly peaked in 1980, leading to legalisation on 2 November 1981. Eventually 40 channels at 27 MHz, plus 20 channels on 934 MHz were legalised.

Australia

In Australia, Citizens Band radio had its beginnings in the 1960s when small numbers of American branded 1-watt “walkie-talkies” started to become available from a handful of outlets. In those days, households were required to hold licences to operate a TV set, but no such licences were available to the general public for the use of 27 MHz band radios.

By the early 1970s CB radio began to gather pace as bigger and better transceivers appeared on the market. As the popularity of CB radio grew in cities such as Melbourne and Sydney, the 27.240 MHz calling frequency became congested at times and users were forced to find other less popular channels to have conversations and to organise an ‘eyeball’ (meeting). The Federal Postmaster-General (PMG Department) was solely responsible for Australian radio spectrum management and radio licensing since the end of World War 2. For the 27 MHz/11-metre band however, the only persons who could legally operate transceivers were licensed radio amateurs who had passed a technical examination, and most had nothing but contempt for the persons operating illegally on the 11-metre band. A small team of radio inspectors began covert surveillance of the “radio pirates” (as they were known) using the 27 MHz band in major Australian cities. Radio inspectors, most of who were licensed radio amateurs, had extraordinary powers in those days and it was not uncommon to hear of or meet CB operators who had been on the receiving end of a visit from overly zealous inspectors with a search warrant. Various State polices forces were mainly ignorant of the illegality of the use of CB radios since it was a Federal jurisdiction issue. CB radios or giveaway antennas were however viewed suspiciously by some individual police who saw them as a means to warn other drivers of speed traps established by the police. Unsure of the legal position, they usually took no further action if they found a CB radio fitted in a car.

By the mid-seventies, a number of CB clubs had developed around Australia including the KT (Kangaroo Territory) Club, the GL Club, Delta Whisky Club and Charlie-Tango club (northern beaches of Sydney), all of whom assigned call-sign numbers to radio pirates interested in ‘joining’ the club. The exchange of QSL cards become popular (like with the licensed radio amateurs), and if atmospheric and sunspot activity was suitable, long-distance ‘skip’ communications could be achieved between pirates thousands of kilometres apart. As the popularity of CB continued to grow, pressure began to be applied to the Federal Government to permit the legal use of the 27 MHz band

The GL Club in the Gippsland region in the State of Victoria was particularly active with representations being made to locally based Federal politicians. Its primary aim was to get CB radio legalised.

On 1 July 1977, after more than two years of relentless pressure from public lobby groups, interstate truck drivers, rural fire brigades and volunteer emergency service units, the Federal Government finally legalised CB radio on 27 MHz with an initial allocation of 18 channels. In 1980 a total of 40 channels was approved for 27 MHz band and it was aligned with the 40 channels used in the USA. From the outset, the Government attempted to regulate CB radio with licence fees and call-signs etc, but some years later abandoned this approach.

After peaking in the 1970s and early 1980s, the use of 27 MHz CB in Australia has fallen dramatically in the last decade. The later introduction of UHF CB Radio (477MHz, 63cm band), using Frequency Modulation for noise reduced signals and the proliferation of cheap, compact handheld and portable UHF transceivers have been a part of the reason.

Over the years there have been repeated attempts by the Federal Department of Communications (now the Australian Communications and Media Authority ) to close down the 27 MHz band.

CB Radio today

CB is still a popular hobby in many countries though its utility as a method of communication among the general public has diminished, due to developments such as mobile phones and Internet chat rooms. CB radio is still a near-universal method of communication among semi truck drivers in America and also remains very popular in rural areas with farmers and hunters, plus sometimes even acting as a sort of "party line" phone system in deep-rural areas too far from major cities to have phone lines. Channel 19 is the most commonly used for this purpose, to the point that some radios even have a dedicated button to bring up channel 19.

Legitimate, short-range use of CB radio is sometimes made difficult by uncooperative users or illegal high-power transmitters, which are capable of being heard hundreds of miles away. Other services, such as Multi-Use Radio Service in the VHF band or FRS and GMRS in the UHF band, exist now to provide the reliable short-range communication service originally envisioned for the Citizen's Band.

The maximum legal CB power output level is four watts for AM and 12 watts (peak envelope power or "PEP") for single side band, as measured at the antenna connection on the back of the radio.

Citizens' Band radios in the United States use frequencies near 27 MHz.

Many radio hobbyists operate illegitimately in the so-called "free band", (which is often referred to as 11 meters, similar to how hams refer to their bands by the approximate wavelengths) using either Citizens' Band equipment that has been modified for extended frequency range and higher power, or else amateur radio equipment operated outside the assigned amateur 10 meter band.

In its heyday in the 1970s, you were likely to find CB Channel 9 monitored by parties who could relay messages to the authorities, or even directly monitored by the authorities themselves. If you are in dire need of help on the road and your only communications tool is a CB radio, you are much more likely to find help on Channel 19.

CB Usage in the United States

In the United States Citizens' Band (CB) radio service is intended to be a private two-way voice communication service for use in personal and business activities of the general public. The Citizens' Band radio services are described in part 95 of the Federal Communications Commission's (FCC) and is defined as a personal radio service.

Eligibility

There are no age, citizenship or license requirements to operate a CB radio in the United States. You may operate on any of the authorized 40 CB channels, however channel 9 is used only for emergency communications or for traveler assistance. Foreign governments and their representatives are not eligible to operate a citizens' band radio station within the United States. You may also operate your US station anywhere in the world except within the territorial limits of areas where radio services are regulated by another agency;

Channel Assignments

To simplify selection of an operating frequency, the Citizens' Band radio spectrum is divided into 40 numbered radio frequency channels from 26.965 to 27.405 MHz, with channels generally spaced 10 kHz apart.

Furthermore, there is a gap between Channel 22 and Channel 23 (which was later filled by Channels 24 and 25) for historical reasons. Before CB was in existence, there was an Amateur 11-meter band from 26.96 to 27.23 MHz, and a frequency for radio-controlled devices at 27.255 MHz. The 11-meter band became CB Channels 1 to 22, and the radio control frequency was shared with Channel 23.

The frequencies for the 40 North American/CEPT channels are as follows:

Channel Frequency Channel 01 26.965 MHz Channel 02 26.975 MHz Channel 03 26.985 MHz Channel 04 27.005 MHz Channel 05 27.015 MHz Channel 06 27.025 MHz Channel 07 27.035 MHz Channel 08 27.055 MHz Channel 09 27.065 MHz (emergency channel) Channel 10 27.075 MHz Channel 11 27.085 MHz Channel 12 27.105 MHz Channel 13 27.115 MHz Channel 14 27.125 MHz Channel 15 27.135 MHz Channel 16 27.155 MHz Channel 17 27.165 MHz Channel 18 27.175 MHz Channel 19 27.185 MHz (unofficial highway channel) Channel 20 27.205 MHz Channel 21 27.215 MHz Channel 22 27.225 MHz Channel 23 27.255 MHz (Note frequencies not in ascending order} Channel 24 27.235 MHz Channel 25 27.245 MHz Channel 26 27.265 MHz Channel 27 27.275 MHz Channel 28 27.285 MHz Channel 29 27.295 MHz Channel 30 27.305 MHz Channel 31 27.315 MHz Channel 32 27.325 MHz Channel 33 27.335 MHz Channel 34 27.345 MHz Channel 35 27.355 MHz Channel 36 27.365 MHz Channel 37 27.375 MHz Channel 38 27.385 MHz (lsb, national calling frequency) Channel 39 27.395 MHz Channel 40 27.405 MHz

The frequency allocation list is supplied by the FCC (Federal Communications Commission) from Part 95 - Subpart D - Rules for CB Service Citizens Band (CB) Radio Service.

In Poland (and probably some other former Warsaw-pact countries) the channels are shifted 5kHz down, so for example channel 30 is 27.300MHz, many operators add a switch that can change between the "zeroes" (the Polish channel assignment), and the "fives" (the International assignment).

Remote Control

Remote control channels

3A	26.995 MHz
7A	27.045 MHz
11A	27.095 MHz
15A	27.145 MHz
19A	27.195 MHz

There is also a Class C Citizens Band service for radio-controlled devices; It has six channels in the 27 MHz band. Radio control transmitters may use up to 4 watts on the first five channels and 25 watts on the last, 27.255 MHz.

The 27 MHz Class C channels are not officially numbered. On the other hand, some CB operators illegally use these channels for voice communications, and usually refer to them by the closest voice channel below them, ex.

Because of interference from CB radios, legal or otherwise, the noise level, and the limited number of channels, most "serious" hobby radio-controlled models operate on other bands.

The Class C service has 50 channels just for model aircraft in the 72.0-73.0 MHz range, and 30 more channels for surface models such as cars and boats in the 75.4-76.0 MHz range. Licensed amateur radio operators also have their own R/C channels around 50 and 53 MHz.

Part 15 and ISM Devices

Most toy R/C cars and most wireless keyboards and mice operate on the 27 MHz R/C channels, especially 27.145 MHz. Instead, they operate under the FCC's Part 15 rules, which allow a wide variety of low powered devices to use the frequencies from 26.96 to 27.28 MHz, which covers CB Channels 1 through 27.

Some other of these toys operate on the 49 MHz Part 15 channels, and often a pair of cars will be sold with one on 27.145 and one on 49.860 to avoid interference.

Another class of devices operating in the 27 MHz band are ISM (Industial, Scientific and Medical) devices regulated by the FCC's Part 18 rules.

Shooting Skip

Although CB radio was only intended to be a short range communications service, the frequencies on which it operates have some very interesting propagation characteristics.

It is recorded that, before CB radio arose, the Afrika Korps in North Africa in WWII used 27 MHz for battlefield communications, thinking that it could only be heard locally;

Finally, it should be noted that under Part 95, Subpart D of the FCC rules it is illegal to engage in, or attempt to engage in communications with any station more than 250 kilometers (155.3 miles) from your location, thereby making it practically impossible for CB operators who wish to shoot skip to remain in compliance with FCC regulations.

Freebanding and Export Radios

Operation on frequencies above ("uppers") or below ("lowers") the established citizens band is referred to as "freebanding" or "outbanding". Many perceive these frequencies just below the CB band, or between the CB band and the amateur radio 10-meter band to be quiet and under-utilized.

This is done with modified CB equipment, modified 10-meter ham radios, foreign CB radios that may offer different channels, or with radios which are purportedly sold for export.

Unlike modified amateur radios which are frequency-agile, export CB's are channelized. Frequency selection on these "export radios", however, resembles that of modified American CB's more than any foreign frequency plan. They typically have a knob and display that reads up to channel 40, but include an extra "band" selector that shifts all 40 channels above or below the band, plus a "+10 kHz" button to reach the model control 'A' channels. These radios may have 6 or even 12 bands, establishing a set of quasi-CB channels on all sorts of unauthorized frequencies.

For example, a freebander with an export radio who wants to use 27.635 MHz would choose Channel 19 ( 27.185 ) and then shift the radio up one band ( + 0.450 ). For instance, Channel 19, 2 bands up, becomes 28.085 MHz, which is in a Morse code-only part of the 10-meter ham band.

Freeband operators have been known to use modified amateur radios that are capable of transmitting on the 11 meter CB band after modification. In newer amateur radios this modification is usually as simple as removing a single part, while in older amateur radios it is often more difficult. Most of the High Frequency Amateur Radios made today have the abilty to transmit on the CB/Freeband frequencys with a simple modification to the radio. It is illegal in the United States (Countrys other than the US have Different rules) to "transmit" on the CB Band with an amateur radio under normal, non-life threatening instances, altho it is not illegal to listen to these frequencys. There are parts of the "freeband frequencys" (26-28 Mhz) that are for use by other radio services, with the proper permits, and/or License.

Adjacent Radio Services

The Business Radio Service has several channels just above the Citizen's Band, at 27.430, 27.450, 27.470, 27.490, 27.510, and 27.530 MHz. This has often been cited as the reason for many of the problems that have plagued the Citizens' band radio service in the past.

In recent years, the FCC has had a renewed interest in taking enforcement actions against freebanding, the sale and use of illegally modified radios and linear amplifiers. This segment includes military, government allocations (26 MHz - 28 MHz) not assigned to the Citizens Band service as well as the Amateur radio 10-meter band (28 - 29.7 MHz).

CB Usage Worldwide

Similar radio services exist in other countries around the world.

In Canada, the "General Radio Service" has the identical frequencies and modes as the United States "Citizen's band", and no special provisions are required for either Canadians or Americans using CB gear while travelling across the border. The United Kingdom, on the other hand, originally had 40 unique 27 MHz channels, known as the 27/81 Bandplan. See CB radio in the United Kingdom.

In the United Kingdom though CB is virtually devoid of activity, a licence is still required, though may soon be withdrawn, but the UK-only frequencies may themselves be withdrawn in 2010 and reassigned to the Community Audio Distribution System service.

Australia now has the 40 North American channels, though previously it had only approved the use of the first 22 channels. With the FCC's minimal enforcement of its rules regarding CB radio, enthusiasts in the USA often use "export" radios, or possibly European FM CB gear to get away from the overcrowded AM channels.

Using radios outside their intended market can be dangerous as well as illegal. For example, the British frequencies clash with a radio service used by ambulance services in Ukraine.

CB Antennas

As 27 MHz is a relatively long wavelength for mobile communications, the choice of antenna has a considerable impact on the performance of a CB radio.

CB in popular culture

Famous CBers

Betty Ford "First Mamma" Muhammad Ali

CB in movies

1974 Dirty Mary, Crazy Larry 1976 The Gumball Rally 1976 Cannonball 1977 Breaker! Breaker! 1977 Handle With Care 1977 Smokey and the Bandit 1978 Convoy 1980 Smokey and the Bandit II 1981 The Cannonball Run 1983 Smokey and the Bandit Part 3 1984 Cannonball Run II 1986 Big Trouble in Little China 1988 Die-Hard 1989 Powwow Highway 1990 Tremors 1993 Dazed and Confused 2001 American Pie 2 2001 Joy Ride 2001 Roadkill 2005 The Dukes of Hazzard (film)

CB radio in music

CB radio appears in several novelty hits in 1976's biggest hits. v • d • e Two-way radio

Amateur and hobbyist
Amateur radio • Citizens' band radio • Family Radio Service
General Mobile Radio Service • Multi-Use Radio Service • UHF CB (Australia) • PMR446

Aviation (aeronautical mobile)
Airband • UNICOM

Land-based commercial and government mobile
Business band • Base station • Mobile radio • Radio repeater • Trunked radio system • Walkie talkie

Marine (shipboard)
2182 kHz • Coast radio station • Marine VHF radio • Maritime mobile amateur radio

Signaling / Selective calling
CTCSS • MDC-1200 • Push to talk • Quik Call I • Selcall