Editing Numbers station (section)

== Identification and classification ==
Monitoring and chronicling transmissions from numbers stations has been a hobby for shortwave and [[ham radio]] enthusiasts from as early as the 1970s.<ref>Māris Goldmanis, [https://www.numbers-stations.com/articles/before-enigma-the-early-numbers-stations-monitors/ Before enigma; the early numbers stations, monitors] NSRIC; retrieved 13 December 2019</ref> Numbers stations are often given nicknames by enthusiasts, often reflecting some distinctive element of the station such as the [[interval signal]]. For example, the "Lincolnshire Poacher" station played the first two bars of the folk song "[[The Lincolnshire Poacher]]" before each string of numbers.<ref>{{harvnb|Mason|1991|pages=20–21}}</ref> Sometimes these traits have helped to uncover the broadcast location of a station.  The "Atención" station was thought to be from [[Cuba]], because a supposed error allowed [[Radio Havana Cuba]] to be carried on the frequency.<ref>{{cite book |last=Poundstone |first=William |title=Big Secrets |page=197}}</ref>{{full citation needed|date=December 2022}}

{{Undue weight|date=January 2023}}

Although many numbers stations have nicknames which usually describe some aspect of the station itself, these nicknames have sometimes led to confusion among listeners, particularly when discussing stations with similar traits. M. Gauffman of the ENIGMA numbers stations monitoring group originally assigned a code to each known station.<ref name="NSRIC">{{cite news |title=ENIGMA: The European Numbers Information Gathering and Monitoring Association |url=https://www.numbers-stations.com/enigma |publisher=NSRIC |access-date=24 February 2015}}</ref>

Portions of the original [[ENIGMA group]] moved on to other interests in 2000 and the classification of numbers stations was continued by the follow-on group ENIGMA 2000.<ref>{{cite web |title=ENIGMA 2000 |url=http://apul64.dsl.pipex.com/enigma2000/ |access-date=1 March 2015 |archive-date=15 September 2009 |archive-url=https://web.archive.org/web/20090915175228/http://www.apul64.dsl.pipex.com/enigma2000/ |url-status=dead }}</ref> The document containing the description of each station and its code designation was called the "ENIGMA Control List" until 2016, after which it was incorporated into the "ENIGMA 2000 Active Station List"; the latest edition of the list was published in September 2017.<ref>{{cite web|date=September 2017|title=ENIGMA 2000 Active Station List|url=http://www.signalshed.com/docs/ENIGMA%202000%20Active%20Stations%20List%20V1.3.pdf|access-date=2020-08-25|website=signalshed.com|publisher=ENIGMA 2000|type=Booklet|version=1.3}}</ref> This classification scheme takes the form of a letter followed by a number (or, in the case of some "X" stations, more numbers).<ref>{{cite journal |journal=[[Radio World]] |year=2014 |pages=14 |last=Friesen |first=Christopher |title=Spy 'Numbers Stations' still enthrall |issn=0274-8541 |volume=38 |issue=2}}</ref> The letter indicates the language 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 languages|Slavic language]].
* V indicates all other languages.
* M is a station broadcasting in [[Morse code]].
* X indicates all other transmissions, such as polytones, in addition to some unexplained broadcasts which may not actually be numbers stations.

There are also a few other stations<ref name="Numbers Stations" /> with a specific classification:
* SK: Digital mode
* HM: Hybrid mode
* DP: Digital-pseudo polytone

Some stations have also been stripped of their designation when they were 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]].<ref>{{Cite web|url=http://www.cvni.net/radio/e2k/e2k032/e2k32e22.html|title=E2K 32 – E22 is not what it seems|website=www.cvni.net|archive-url=https://web.archive.org/web/20071117095441/http://www.cvni.net/radio/e2k/e2k032/e2k32e22.html|access-date=2016-04-05|archive-date=17 November 2007}}</ref>