Citizens Band radio

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Break One Nine, Break One Nine, You got a copy?

CB Radio is a two-way radio service within 40 channels defined by the FCC on the 11 meter radio band. Class D Citizen Band radio began in 1958 with 23 channels defined in the 11 meter band. 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. The Citizens Band Radio Service is for short-distance voice communications service for individual or business activities. The CB Radio Service may also be used for voice paging.

  • FCC License: No
  • Max Output: 4 watts
  • Frequency: 11 meter (HF)
  • Band: 3-5 kHz
  • FCC Reg: Part 95

The use of CB radios in 1970s films such as Smokey and the Bandit (1977) and Convoy (1978), popular novelty songs such as C.W. McCall's "Convoy" (1975) and on television series such as Movin' On (debuted 1974) and The Dukes of Hazzard (debuted 1979) established CB radio as a nationwide craze in the USA in the mid- to late 1970s.

CB Radio channel 9 was officially reserved for emergency use by the FCC in 1969. In 1977 the CB Radio channel selection was expanded from 23 to 40 channels. Channel 19 became a nationally recognized channel for Truck Drivers. Many CB Radio users called channel 19 "the trucker's channel". Channel 11 was originally restricted by the FCC for use as the calling channel.

Output power is limited to 4 watts and CB radio is AM (Amplitude Modulated), however, (SSB) is allowed up to 12 watts of transmit power.

CB has lost much of its original appeal due to development of mobile phones, the internet and the Family Radio Service. Changing radio propagation for long-distance communications due to the 11-year sunspot cycle is a factor at these frequencies. In addition, CB may have become a victim of its own popularity; with millions of users on a finite number of frequencies during the mid-to-late 1970s and early 1980s, channels often were noisy and communication difficult. This caused a waning of interest among hobbyists. CB radio is still used by truck drivers, and remains an effective means of obtaining information about road construction, accidents and police speed traps in the United States.

Frequency Table

  • 1 26.965 MHz
  • 2 26.975 MHz
  • 3 26.985 MHz
  • 4 27.005 MHz
  • 5 27.015 MHz
  • 6 27.025 MHz
  • 7 27.035 MHz
  • 8 27.055 MHz
  • 9 27.065 MHz (Emergency Use)
  • 10 27.075 MHz
  • 11 27.085 MHz (Calling Channel)
  • 12 27.105 MHz
  • 13 27.115 MHz
  • 14 27.125 MHz
  • 15 27.135 MHz
  • 16 27.155 MHz
  • 17 27.165 MHz
  • 18 27.175 MHz
  • 19 27.185 MHz (Truckers Channel)
  • 20 27.205 MHz
  • 21 27.215 MHz
  • 22 27.225 MHz
  • 23 27.255 MHz
  • 24 27.235 MHz
  • 25 27.245 MHz
  • 26 27.265 MHz
  • 27 27.275 MHz
  • 28 27.285 MHz
  • 29 27.295 MHz
  • 30 27.305 MHz
  • 31 27.315 MHz
  • 32 27.325 MHz
  • 33 27.335 MHz
  • 34 27.345 MHz
  • 35 27.355 MHz
  • 36 27.365 MHz
  • 37 27.375 MHz
  • 38 27.385 MHz
  • 39 27.395 MHz
  • 40 27.405 MHz

CB 10-codes and Q-codes

Shorthand communication on CB radio, the ten-codes, officially known as ten signals, are brevity codes used to represent common phrases in voice communication The CB Radio 10 codes are not the same as those used by law enforcement.

The Most Commonly Used 10 Codes for CB Radio:

  • 10-1 Receiving Poorly
  • 10-4 Ok, Message Received
  • 10-7 Out of Service, Leaving Air (you're going off the air)
  • 10-8 In Service, subject to call (you're back on the air)
  • 10-9 Repeat Message
  • 10-10 Transmission Completed, Standing By (you'll be listening)
  • 10-20 "What's your location?" or "My location is..." Commonly asked as "What's your 20?"
  • 10-100 Out of Service to go to the bathroom.

The Most Commonly Used Q Codes by CB Radio Freebanders:

  • QRM man made noise, adjacent channel interference
  • QRN static noise
  • QRO increase power
  • QRP reduce power
  • QRT shut down, clear
  • QSL confirmation, often refers to confirmation cards exchanged by hams
  • QSO conversation
  • QSX standing by on the side
  • QSY move to another frequency
  • QTH address, location
  • CQ-DX - Skip (or DX) is a name used to describe atmospheric conditions that allow for radio transmissions to travel long distances. The CB radio frequency spectrum is located very close to one of the popular Ham Frequencies used for DX. CQ is a radio term meaning "Calling any station." When used as CQDX the meaning is calling any distant station. Legal AM CB Radio is not capable of utilizing skip in a practical sense. However, using 12 watt sideband it is possible to communicate long distances and therefore a sport has been built around making long distance contact "DX" on legal "bare foot" SSB CB Radio.


Bootleg CB Radio is the use of Citizen Band radio in a way that does not comply with FCC regulations. The most common form of illegal use is the use of transmit power that exceeds 4 watts on AM or 12 watts on SSB.

SideBand (SSB) is a mode capability found in higher-end CB Radios. Access to the Upper & Lower Sideband Modes (USB, LSB), can be found on each of the 40 channels, in addition to the "Regular" (AM) mode.

Some frequencies outside the legal CB range can be achieved by a modification to many CB radios. Channel examples:

  • 27.555 USB International Call Frequency
  • 26.285 USB International Call Frequency

Other modifications include increasing the output power and increasing the modulation. Additional transmit power can be achieved with a linear amplifier. The use of certain HAM radios on CB frequencies at power exceeded the legal amount is another way individuals bootleg.

Mobile Ham operators all over the U.S. are observing and reporting truckers talking above 28mhz and will report them to the FCC.

CB Performance Folklore

Michael Rawls of put it best when he said, "Most CB'ers are clueless about radio theory. The CB band is filled with average joes with no formal electronics training trying to guess at radio theory. As a result, nonsense CB folklore has filled the airways for decades. If you actually start cracking the radio theory books and start learning legitimate radio theory you will be quickly outnumbered by CB'ers who have no clue what they are talking about. They will argue with you until h*ll freezes over, and they will be wrong the whole time."

Read: Lets Explode a Few CB Myths

Sparks flying from antenna's with linears, Cobra mobiles modified to double and triple their output, voice modulation that drives the signal harder, and the Antron 99 is the miracle antenna of the universe...

For entertainment, a CB operator known as "The Duke" used to claim to be in foreign countries while talking to CB'ers and they were convinced they were working the world on their little modified (or electronically butchered) CB radio. It is easy to see how some myths get started.

Michael Rawls does introduce some interesting facts about antenna gain. "On the 27 MHz CB band, the taller a vertical omni directional antenna the higher the gain up to about 23 feet. [...] The highest real gain omni-directional CB antennas currently on the market are the full length 5/8 wave. [...] 5/8 wave and .64 wave antennas also have a much lower angle of radiation than 1/2 wave and 1/4 wave antennas. A low angle of radiation really pays off when trying to talk to distance skip station in excess of 1500 miles. "


See also:

External Resources