Ofcom are the regulatory body with the UK.
All amateur radio operators, wherever in the world they are based, are required to hold a special licence and to obtain this; they must pass an examination, showing that they have a good basic knowledge and understanding of the main concepts involved in this highly technical activity. In particular, the relevant administrative authority in each country must ensure that applicants can demonstrate reasonable technical knowledge as well as operating competence and a working knowledge of the legal and regulatory requirements, to ensure their non-interference with other amateurs and commercial radio services.
Most countries provide for a graded series of examinations for aspiring amateur radio operators, which are designed to become progressively more complex and challenging. Success at each level will reward the applicant with an enhanced license. The operator is then granted access to better frequency allocations, and allowed to use increased power output, and may be permitted to carry out experimentation and, in some countries, be allocated distinctive “callsigns”. When issuing a licence, the relevant national authority will also provide the operator with a unique callsign. This callsign is used on air to identify the operator, and to show that he or she has a legal right to undertake radio communication. The user must use the callsign during all communications. In the UK callsigns are currently assigned as follows, the licence Level prefix followed by your own 3 letter identifier;
M6??? = Foundation max power 10 watts
2E0??? = Intermediate max power 50 watts
M0??? = Advanced max power 400 watts
You may also hear special event or club callsigns such as GB2SUN (a solar powered operator)
Some users may decide to use a “vanity” callsign, which in some jurisdictions, (such as the United States), may be obtained by payment of a fee, but in others, (such as The UK), a vanity callsign is free of charge.
Different prefixes are used for different countries within the UK for England, Ireland, Scotland, Wales and the Channel Islands, but you’ll learn more of that as you undertake your licence.
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