Directional antennas.

Directional antennas are illegal for use on UK CB.

Directional antennas will send more signal in one horizontal direction than in others.
These may be useful if you are trying to contact a certain person or country - you point it in their direction. This extra signal in their direction means that less signal will go out in other directions - you will still only be sending the same amount of power, just concentrating it in that direction.

For CB use, such antennas are usually pointless, as the service is designed for general chat to others who may be on there in your local area and this means that you need to be able to sent and receive in all directions.

To use a directional antenna, you also need a rotator, which will turn the antenna round in different directions. Usually, this will take the form of a motor which physically turns the antenna. Some have been designed which can change direction electronically by correct phasing of the signal in different sections. Such antennas do not need to be physically moved to change the direction.