Radio amateurs are individuals who have undertaken an examination to prove competance in the use of radio transmitters. They are licensed to operate on a number of allocated bands in the Radio frequency spectrum. The power of their equipment is restricted, and they must not cause interference to the reception of authorised broadcsasts. They may not broadcast themselves, or communicate with the public with their equipment. They are only allowed to communicate with other licensed operators. They are issued with a unique identifying call sign which must be sent at intervals during their transmissions. They are regulated by an International body which agrees the allocation of channels available to each individual country or region of the world.
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