Most of the number stations have been given nicknames which usually describe some part of the station itself, M. Gauffman of the E.N.I.G.M.A. number stations monitoring group originally gave a code to each of the known numbers stations. This takes the form of a letter followed by a number (or, in the case of some “X” stations, more letters). The letter indicates what language is being used by the station in question:
- E indicates a station broadcasting in English.
- G indicates a station broadcasting in German.
- S indicates a station broadcasting in a Slavic language.
- V indicates all other languages.
- M is a station broadcasting in Morse Code.
- X indicates all other transmissions which may not actually be numbers stations.
- T indicates a station broadcasting in an unknown language.
For example, the well known number station, The Lincolnshire Poacher station has been designation E3 (or E03), and the Cuban “Atención” station has been designation V2 (or V02). The most recent station to be given a designation is M94, which is believed to be sent from South Korea.
Some stations have also been stripped of their designation if they are discovered not to be a numbers station. This was the case for E22 which was discovered in 2005 to be test transmissions for All India Radio.