CB Radio Usage in the United Kingdom

CB Radio was introduced for the first time in the UK in 1972. CB radios were originally just used around the airports, though illegal CB radios were often imported from the United States and used for unauthorized broadcasting in the UK. This illegal use was at its height around 1980, which was about the time when the UK government was forced to legalize the use of CB radios for private use.

CB use was made legal to the public on November 2 in 1981. Since then, the use of CB radio by private citizens remains legal, as long as the CB equipment meets with the government standards. For one, the equipment may not exceed 4 watts of power, and may only broadcast on the FM band.

There was a lot of debate around that time as to exactly what frequency range should be used for CB radio. Ultimately, CB  radio was legalized on a 27 MHz band, which was what the CB radio users actually wanted. However, it came with a hitch.

First, it did not use the same band as the United States (26.965 to 27.405 MHz). It was going to use on 27.601 to 27.991 MHz, and was going to have a power limit of 4 watts. However, antenna restrictions further reduced the power that UK citizens were allowed to broadcast at, limiting most CB broadcasts to a maximum power output of 500 mW.

Since that time, another block of frequencies on the 27 MHz band gave UK CB radio users 40 more channels, but all of the other laws, requirements, and restrictions have remained the same. In actuality, U.S. CB equipment is usually illegal to use in the UK. The height of antennas is also regulated, though not usually policed or enforced.

Additional detail can be found at: http://en.wikipedia.org/wiki/CB_radio_in_the_United_Kingdom.