From the archives: The numbers station game Part 1

one time pad image:

With an increase in interest in numbers stations of late I thought I'd reprint my 3 part article I wrote for Radio Active magazine in 2001. Links and frequencies may be out of date- and it was written when broadband was in a minority of UK homes- but it may still an interesting read for some people ... Part 1 of 3.

Amidst the cacophony of sound on the short wave bands, a strange and mostly unexplained phenomenon has existed since early last century. On the non-broadcast bands, away from the ears of the average listener, there exists a mysterious set of transmissions. Tune in to certain frequencies on the fringes of the broadcast or utility bands at the top of the hour, and you won’t hear a station identification followed by a news bulletin as you might expect. 
Instead, sometimes preceded with a signature tune or Interval Signal, but as often not, a voice will emerge, reading not a political opinion or sports results, but a series of numbers.

Welcome to the strange world of number stations. This is the first of a series of articles that will give you a flavour of what is probably the biggest mystery on the bands. This month there will be an introduction as to what you might be able to hear on your receivers, and explanations as to what they are assumed to be. Next month we’ll delve further into the field and show you ways to access all the information on numbers stations via Internet sites which have been set up by some of the many individuals and organisations who keep a tab on them. So there should be something for newcomers and Numbers stations veterans alike.

Some ascertain that numbers stations began during World War One as spy chiefs sent coded messages to their agents via radio. So what can you expect to hear at the dawn of the 21st century? The numbers stations are allegedly spy stations and consist of a series of random numbers being read out, in English, Spanish, German, Arabic and other languages, by men, women and sometimes even a child. (the latter being a station known as ‘Swedish Rhapsody’ consisting of a girl reading a list of numbers in German). Sometimes it is in morse code, sometimes just noise. One station has transmitted a continuous buzzing sound for years. Usually the voices are mechanised, sometimes they are read out live. This has led to tales of announcers who are the worse for drink slurring their numbers, and of a Spanish speaking numbers station being intermingled with Radio Habana, supposedly a give-away to the station’s location, or maybe a double bluff? As you would expect in such a sphere of mystery and suspicion, urban myths can spread, adding to a confusing and unquantifiable situation.

If you have been listening to the short wave bands for years, you will undoubtedly have come across a numbers station at some point (also sometimes referred to as spy stations). When I first stumbled across them in the 1970s, I just assumed they were either weather beacons or just another form of the many squeaks, gurgling and static noises that you encounter, assuming them to serve a mundane purpose rather than anything sinister. I’m sure I am not alone in that assumption.

Newcomers to the radio hobby may think that such strange goings on, with numbers being transmitted in different languages across the ether, were a product of the cold war, (which many were), and would have long since faded away. However, over a decade after the collapse of the Berlin Wall, the monotonous voices continue as regularly as ever. As well as messages from organisations such as the CIA, MI6, MOSSAD (the Israeli equivalent), some say there is activity in the field of industrial espionage too, with individuals working for transnational corporations maybe taking calculated risks to sell product information to a rival company.

The stations are basically broadcasting a secret code and at first sound or sight they appear to be a random set of numbers harking back to the realms of schoolboys secret agent games, days of home-made invisible ink made of lemons, and simple codes with numbers corresponding to a letter, decipherable within minutes.  However, these broadcasts are assumed to be the work of government agencies, transmitting messages to agents in the field. Each agent is assigned what is called a one-time pad, a series of numbers, one copy for him and one for the transmitter base. Then the agent simply has to tune in to a frequency at the right time, note down the numbers being transmitted, and decipher the message.

In these days of highly developed and diverse forms of communications, the idea of a mechanised voice reading out codes which are to be received via a radio-set must appear incredibly old-fashioned. It is such a hit and miss affair after all, subject to propagation or interference from other signals on the bands. The agent the transmission is aimed at might not be at his receiver at the designated time, may incorrectly transcribe the code or just fail to hear it all. There is no way of knowing if the message has been received correctly.
So why not send an encrypted email, or a text message via phone, or use one of the many other forms of modern communication in this high-tech age? Well, the beauty in using short wave is there is no way of identifying the receiver, or the agent in the field. If you have the resources and the right government organisation behind you, it is easy to obtain details of emails or telephone messages that have been sent. Where telephone lines are monitored by the secret services certain patterns could emerge with a minimal amount of work. For instance, why does a telephone line rented by a plumber in a Johannesburg suburb receive a call originating from a State Office in Copenhagen lasting 20 minutes every third Thursday at 3.30 a.m?

So whilst broadcasters and utility band services, the regular users of short wave, increasingly look towards satellite and Internet to reach their audience, the spy scene continues to make use of a tried and tested medium. Messages are sent often and repeated, giving the recipient opportunity to ensure the message is correctly received.

Messages are transmitted by stations as regular as clockwork, day after day, year after year, and often consist of dummy messages. This is because were a station to transmit only when it had vital information to send, it would be easier to identify in times of crisis or political upheaval.  An increase of traffic on the bands that coincided with a civil uprising in Bratislava could indicate that certain Numbers station frequencies were emanating from Slovakia.

Years of painstaking loggings and recordings by hobbyists has resulted in a highly developed network of monitors across the world, such as ENIGMA, which stands for the European Numbers Information and Monitoring Association, and is not to be confused with the Enigma code breaker machines used to such effect at Bletchley Park during World War II.
Officially the Numbers stations ‘don’t exist’, but those who operate them are aware of  the groups of radio hobbyists who listen in. They are probably considered a mostly harmless group that can be contained without any real threat to security. The proportion of the population that listen to short wave in the developed world is small, fewer still would listen to Numbers stations, and even fewer are likely to develop an interest in them. Even if a transmitter location is identified through piecing together loggings and signal strength, the codes themselves remain next to impossible to crack.  Despite the coverft activities of operators, one unique station that transmits from what was Czechoslovakia, has actually verified a reception report by issuing a QSL card! Maybe this was an act of arrogance, or humour, as a simple acceptance of ‘we know you know but so what?’

In 1997 The ‘Conet Project’ CD was issued. This is a 4 CD set of shortwave Numbers stations recordings assembled by enthusiasts, and gives a fascinating overview. They have a website which gives more information, but we’ll have a look at that next month. As well as giving all the information and links to Numbers stations that you would probably ever want, there is also an ongoing competition which invites you to try and crack the codes of various stations. I’ve reproduced one of them here as an example.

This is a transcription of an E22 transmission, recorded on August 14th 1997, frequency 8024 lower side band. E22 has since been given the designator ‘Arabic Man’.

04090 03403 29286 20356 38122 33628 55375
52145 01500 99398 83458 04554 59754 96338
86434 49249 93679 64770 62798 19244 44996
19794 49378 27271 80437 14363 98605 24798
56999 85443 72665 99182 64776 49871.

It is surprising how rarely Numbers stations are mentioned in the press. When you consider the amount of airtime and column inches given over to ‘unexplained’ phenomena such as crop circles and UFOs, Numbers stations are never investigated to such depth, if at all, yet they can easily be heard by one and all with minimal effort and equipment but go unnoticed.
In 1999 The Daily Telegraph reported a spokesperson for the Department for Trade and Industry as saying the following about Numbers Stations: ‘These are what you suppose they are. People shouldn't be mystified by them. They are not for, shall we say, public consumption’. This in itself is quite revealing.

Another rare piece of mainstream media exposure was when John Walters did a mainly light hearted report for the BBC 1 programme ‘Here and Now’ in April 1997. The most interesting quote came from ex-KGB Station Chief Oleg Gordieiski who stated ‘The messages are a mixture of professional instruction, what to do next, and some personal messages from children, parents and friends. For example, Mr Gorbalov, next week please go to Vienna and use dead letterbox number 13. You will find 8,000 American dollars. It is your salary for the next month, and the rest for your operational expenses.’

In an attempt for fellow hobbyists to identify them, Numbers Stations have been given nicknames by short wave listeners over the years, according to their output style or manner. For instance, two of the best known are run by British Intelligence Forces; The Lincolnshire Poacher and Cherry Ripe, and are named after their prelude tunes. ENIGMA made the identification process easier by assigning each station a designated number, to accompany the commonly used nickname.

Other details in the list include the suspected transmission site where known, description of the announcer (YL- Woman, OM- man), and the Intelligence Agency operating the station.

ENIGMA designators, The following list illustrates some of the English speaking stations on the ENIGMA list. Full lists can be found on the web, of which more details next month. ENIGMA 2000 is a spin off group from ENIGMA, and is on the web at

E01       Ready Ready YL/EE                                     
E03       Lincolnshire Poacher YL, MI6, probably Cyprus
E04       Cherry Ripe YL/EE, MI6, probably Guam                
E05       Counting Station YL/EE                               
E06A    English Man 2 group commencing with stutter group    
E07       English Man OM/EE                            
E09       Magnetic Fields YL/EE                          
E10       Phonetic Alphabet Station YL                         
E13       5 Dashes YL/EE                                        
E14       Count Control YL/EE                                  
E15       Nancy Adam Susan YL+OM                               
E17A    English Lady. Dual message                           
E20       English Lady. Dual msg format of E17 or E6 YL/EE     
E22       Arabic Man 2L/F (FD7, FD9)                           
E23       3 messages per month 100/100/50GC                    
E24       'Allo allo'                                          

Bizarre and intriguing stations in other languages include the Morse ‘Rapid dots tuning signal’, Spanish ‘Bored Man’, Polish 'Zyt Zyt' (Hush hush), German ‘3 Note Oddity’, Romanian ‘Skylark’, ‘Guangzhou calling’ and a whole series of noise stations, such as Bugle, Six Notes, Crackle, Polytone High Pitch and Plaintive mew.                                                                

If this has whet your appetite then try listening in. Here are a few times and frequencies to start you with:
Lincolnshire Poacher, 1700-0000 UTC on 5746, 6900, 6959, 9251, 10426, 11545, 12603, 14448, 16084 KHz

Cherry Ripe: 1300 UTC on 14496, 17499, 18864,19984, 20474, 21866, 22108, 23461, 24644 KHz

Backwards Music station: 2100-2300 on 5178, 6753 KHz

DEA 47 Morse (from Northern Germany): 0800-1000 on 12283, 13510 KHz

More information on recordings that are commercially available, as well as audio samples you can hear on the Internet, will be given next month. I’ll also be investigating some of the websites set up to disseminate information, and sometimes mis-information, on Numbers stations. I’ll take a look at a station known as ‘the razzer’ and an FBI agent’s view on a project named ‘Carnivore’. There are various discussion groups, links to government bodies and sites, societies and clubs set up to discuss the subject and plenty of individual sites which range from the informative to the unbelievable.
 (ENIGMA list with thanks to Ary Boender).