Number Stations

That was because a wartime oath of silence had prevented all those involved in the secretive work, Englishman, European and American alike, from making any open reference to the huge operation in breaking enemy codes.

In 1974 Group Captain Winterbotham was authorised to publish his book, 'The Ultra Secret,' which was an immediate hit with the public. It was popular to the extent that 3 copies were observed being read in a single train journey in London shortly after its release.

From 1977 HM Government relaxed its view of these secretive occurrences and radio and television programmes adequately covered the subject to the point that the existence of the 'Y' Service, those who sat at short wave receivers, who intercepted enemy messages for decoding by Bletchley Park was acknowledged.

These 'Y' Service operators were like secretive, with a good proportion of women amongst their ranks. In addition to the full-time operators there were also the part-timers, the Radio Security Service's amateur radio operators. These persons hurried home of an evening from their reserved occupations [there is another side to this, but beyond the scope of this piece] and using their receivers trawled the short wave spectrum, to set schedules, for messages to and from the German military or occasionally from the odd German agent who might be operating from British shores.

Of the coded signals that could be intercepted some would take this form. Sent in Morse:

HRQN SMAD LVIO DMMW JLKN
GSRJ VNLC IKGT MDRB IDAW
YLIK IFIF CMCG HRQN HRQN

The first and last two groups show the encipher message key, albeit encrypted. The actual message to which this example* refers was sent on 30th April, 1945 [*Taken from an example within Enigma-e User Manual. Details of the excellent kit at http://www.xat.nl/enigma-e/ ]

An Enigma machine

The above ENIGMA enciphered message is similar to many Number transmissions that can be intertcepted daily, save for the use of four character groups. [E25 is a modern station that uses four character groups, and believed to be of Arabic origins].

During the 1970s it was relatively simple for anyone with a short wave receiver to intercept a host of number stations using Morse or Voice. There were various traits to be used to identify the whole variety of stations, but not to any accuracy.

As the Cold War continued to its eventual conclusion the transmissions were never ending, the STASI were responsible for many sendings regularly heard. Some were annoying as they popped up in the 80M band, a harshly toned female reading German numerals intefering with the interests of SWLs and licensed amateurs alike. But these stations were everywhere. Except to those who were the intended recipient and those who listened specifically either with interest or with National security in mind, some appeared to have regular schedules, others seemed to pop up, send a message, then disappear.

As the Berlin wall toppled and signalled a new beginning to the world order those of us with an interest in Number Station transmissions assumed that many stations would not be heard again, whilst other schedules might well fade away with time.

The situation could not have been different; today the Number Station transmissions still dominate the short wave. Anyone who tunes around out of idle interest will encounter the transmissions. Others who tune up waiting for a broadcast station to appear may be rewarded with a few groups of figures being sent prior to the rightful occupier of that freq appearing, unfortunately such a catch is often thought of as being annoying by the unwitting BC listener.

A typical and very common voice transmission to be heard would take this form as the female operator chants out the NATO phonetics for each character Uniform Lima X-ray etc:

'ULX ULX ULX (repeated)
MESSAGE MESSSAGE
GROUP 29 GROUP 29
TEXT TEXT
AONZA LINOB HVOJP KFOQS ZNMSA ENKEV TOQYD TSVIM GAUAR ULWDY
MGMNK OGHXY OYGMN NECQC RGBSP JTQYN WFVMW MBMNX QWURN BAPWX
JYVMN DYYRO PZYGA UUOEC FQJQQ SYTRP BMPKC RAPEM KNIWO
END OF MESSAGE, END OF TRANSMISSION'
Apart from the use of alpha characters E10 has another identifying trait, the pronunciation of the phonetic for N. NovemBEAR, with the 'R' being partially rolled.

This message was intercepted by E2k monitor IW, on 4880kHz 2000z 14/04/2004 and is thought to have originated from the MOSSAD, the Israeli secret service. Their transmissions are, by far, the most commonly logged station in the US.

Another easy to hear voice station is believed to originate from Cyprus and introduces itself by sending the first few bars of the English folk tune 'Lincolnshire Poacher' followed by a five figure group. Those transmissions can be intercepted between 1200z to 2200z daily.

A similar station uses the same format but uses a few bars of 'Cherry Ripe'. Unlike its sister station the schedule lasts Monday to Friday between the hours of 0000z and 0100z, 1000z and 1300z plus 2200z and 2300z. It is believed that the transmissions are sent from Guam and as such only those between 1000z and 1300z have been logged in Great Britain.

ENIGMA 2000 monitors in Australia and New Zealand report the transmissions we cannot hear and one of our best reports was from a member in Brunei BFPO11. The voice for these two transmissions is a 'plummy' female public school type accent; it has been suggested that these stations operate on behalf of MI6. It is for that matter that ENIGMA 2000 do not report on these stations as we would not wish to be instrumental in supplying information to those whose Great Britain's best interests are not closest to its ideology.

The purpose of these stations has always been denied by successive governments but two British spying cases exist that actually give their purpose away. A third and recent American case proves the link to spying but also illustrates changes within the structure of the agents' equipment. Prior to these cases explanations offered went from the sublime to the utterly ridiculous. It was reasonably suggested that the transmissions were coded 'caught fish quotas' being sent to the various trawling companies, whilst another theory suggested that drug dealers were communicating in code. But the best and most stupid suggested that certain governments were communicating with flying saucers!

The three stations mentioned above send in English language but other languages are also used; German, Russian, Slavic and Spanish being the most common. There are also stations that use Korean dialects and Arabic has been heard as well. However the number of Morse transmissions far outweighs those by voice and there are a number of data systems in use too.

A classification scheme was devised by the founding members of the now closed ENIGMA.[SWM has a column penned by ENIGMA, 'Attention123' which appears on a bi-monthly basis]. The ENIGMA Control List became the de facto listing available, within the interest, to enable identification of stations by their traits. The stations mentioned above have the classifications: 'Mossad' E10, 'Lincolnshire Poacher' E03 and 'Cherry Ripe' E03a. The Slavic and Russian stations use 'S' as their designation, German 'G' and the Spanish and a variety of other languages 'V'.

Morse transmissions use the designation 'M'. The ENIGMA Control List is kept current by ENIGMA 2000 and is available for download from its group site.

As mentioned previously, various persons, as well as the occasional journalist, questioned the purpose of the number stations and as ever the replies from successive governments brought denial or occasionally the sort of explanation mentioned before. Obviously during the days of the Cold War one could feasibly understand this reticence given that the world powers were 'at it' with a will. There never has been a satisfactory answer to the question save the apparent faux pas by a government representative [from the Department of Trade and Industry] who remarked to an inquisitive Daily Telegraph journalist that these stations are "what you suppose they are, people shouldn't be mystified by them. They are not for, shall we say, public consumption."

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