Number Stations During the Cold War (Part 3)


In the third, and final, part of his short series on the number stations mystery, H.J. Hagermann gets up close and personal

In the third, and final, part of his short series on the number stations mystery, H.J. Hagermann gets up close and personal with the voices and people behind the number stations during and after the Cold War.



In East Germany (The German Democratic Republic, GDR) controlled by the ‘Stasi’ (Staatssicherheitsdienst, the Secret Police), there was a lady who was widely credited with being the live announcer in the early East German Number stations transmissions (Fig. 1).

She was eventually replaced by a multi-voiced, ROM-based, machine but not before she was photographed. Was this, in fact, ‘Magdeburg Annie’? (RadioUser, June 2018: 46 to 49).

Alas, we do not have her name but the credit for this picture goes to Detlev Vreisleben, who has written some very interesting and well-informed articles for us at the ENIGMA2000 group (E2K).

Judging by the two stud marks on the photo, it has been copied from a National or Service Identity Card.


After the Wende

As we already know, the GDR shut down its clandestine radio stations shortly after the opening of the Berlin Wall on 9th November 1989, which marked the ‘Wende’ (‘Turning-Point’) in postwar German history.

This is how the West German Press Agency (DPA, Deutsche Presseagentur) described that event:

"They (the stations’ transmissions) were always preceded by a gong being struck several times. Then, on the short wave frequency of 3220kHz (really 3258kHz) you could hear a ‘synthetic’ voice, speaking in a ‘metallic tone’, uttering combinations of numbers in groups of five…

“This conveyed ‘coded’ news from East Berlin to agents in the Federal Republic of Germany (West Germany, the FRG) and in neighbouring foreign countries. On this day too, once again, the routine broadcast was expected by the FGR counter-intelligence service for Thursday evening, but it never came.

“The voices of espionage had fallen silent."


Shady Ladies

Well, not quite silent. The voices of the number stations in West Germany (The Federal Republic of Germany, FRG) carried on much longer, although, obviously, they were now directed at different targets.

In August 1989, a few months before the final fall of the Wall in September, I encountered Delta Foxtrot Charlie Drei Sieben (37) and my numbers interest really took off.

My first logging of this ‘Shady Lady from the BND’ (as she was known, I was to later to learn) is down in my log for Sunday, 21st August 1991, at 2304 UTC. The format for these stations was always the same:

First, there were musical notes, interspersed with the callsign or a Net Identification Signal (NIS).

These markers were repeated many times over.

I soon got much more deeply into this numbers game. I recalled how the SIGINT guys had carried out traffic analysis and callsign-comparisons. In this manner, they had made out transmission schedules (‘skeds’) of the various stations, which we monitored.

Not that I was ever a signals traffic analyst. My only claim to fame was being fluent in German.

Soon, I was making out skeds of transmission times for my new-found friends, and I was loving it.

Lists of callsigns for comparison followed, along with mode comparisons. Although my rig was only a superhet, even I knew that – if it sounded like Donald Duck in a Scuba kit – then it was a good bet that the mode was SSB.


Operational Similarities

I soon realised that there were several stations, all similar in their mode of operation. They were DFC37, DFD21 and Papa November. I remember thinking at that time that these were probably all part of the same network or organisation. And very professional they were!

The style never varied: It began with ascending musical notes, followed by the German YL, revealing what I used to call a Net Identification Signal or NIS. After this, she would call up some three-figure callsign and announce how many groups of text were intended for each station.

Typically, this is what was sent:

DFC37, DFC37

Then would follow the musical notes.

This was repeated many times.

After this, the announcer would say (and here there is some contradiction) “Es folgen Mitteilungen für…” (“There now follow reports for” …) I have been told by monitors who have studied these stations more deeply than I have (and who are German, monitoring them in Germany) that that is what was said.

However, I have tapes of the stations I monitored at the time, in which, I am certain, that the actual words spoken were, “Es folgen Sendungen für…” (“There now follow transmissions for…”).

Not much of a difference: “Whatever”, as my Oregon cousin Byron would say.

After the ‘preliminaries’, the mystery-lady would announce which three-figure callsigns were to receive traffic in that particular sending group. Thus, a full announcement would read, for instance, as follows:

“DFC37: DFC37: Es folgen Mitteilungen (Sendungen) für: 274: 274: 40 Gruppen.”

 After this, and once all call signs had received their stand-by call, it went on like this:

“Achtung! 274: 274: 40 Gruppen!” (“Attention! 274:274: 40 groups!”).

And following this, the transmission of the five-figure groups of numbers would be read out and repeated.

If there was no more traffic, she would terminate the transmission with “Ende!”  

Papa November is another of the stations, which figured frequently in my logs of these years.


Papa November (G15)

The Papa November network used more than 80 callsigns on almost 40 different frequencies. This would indicate a large network, serving many users or agents. The earliest monitoring of this spy net goes back as far as the early 1970s.

In this net, the initial call-up consisted of a female voice repeating ‘Papa November’ continuously, with a flute playing in the background. This lasted five minutes.

Then a woman started sending messages in five-figure groups.

The messages were read by a real female voice, which continued until 1989. This would be recorded, and the tape could then be transmitted at the appropriate time.

Off-the-air noises, pauses in reading and other clues indicated the use of human readers.

In 1989, these human readers were replaced by voice-synthesizers such as the Sprach-Morse-Generator, shown in Part Two of this series (RadioUser, June 2018: 46 to 49).

The frequencies in use were 2707, 5015, 7404 and 11108kHz. This choice of frequencies, over a variety of bands, ensured maximum propagation.

The schedule was designed to give a wide geographic coverage. Messages were sent every day, including Christmas, at 0000, 0030, 0600, 0630, 1200, 1230, 1800 and 1830 UTC. The transmissions on the hour were in AM mode, whereas the broadcasts on the half hour were all in USB.

The inner workings of traffic analysis can be illustrated by using this station (G15) as an example: The number of messages changed considerably. Sometimes there may be only have been five messages, at other times perhaps ten.

More than likely, the changes in the volume of traffic related to events in the real world. Obviously, this requires a comparison of world events on the one hand and the volume of traffic, length of messages, number of different call signs used, transmission frequency and other factors, on the other hand.

It was also significant to know whether or not a message was repeated because this would indicate a certain urgency of that message.

Of course, it could also be a training message, we just cannot be sure. This is what traffic analysis is all about. As an old friend of mine once summed up, “You have to guess right!”

Of course, Papa November was not listed in any available frequency list and its callsign was not issued by any telecommunications authority.


Call Signs DFC37 and DFD21

The Papa November callsigns were heard on two frequencies, 3370kHz for DFC37 and 4010kHz for DFD21.

They were identical in operation and in message output.

In the early 1970s, ten descending notes would precede transmission, after which a woman was saying,

"Hier ist DFC37" or "Hier ist DFD21". (“This is DFC37” or “This is DFC 21”).

With the increasing use of the synthetic voice generator (Sprach-Morse Generator) the interval signal was changed to electronic tones. This was followed by a woman announcing:

"Delta Foxtrot Charlie Drei Sieben", or

"Delta Foxtrot Delta Zwo Eins."

 [‘Zwo’ is another way of saying ‘Zwei’ (‘Two’) in German, for clarity, lest it be confused with the similar-sounding ‘Drei’ (‘Three’) in a voice transmission – Ed.].

The schedule was as follows:

DFC37: 3370kHz – 1500 to 2200 UTC

DFD21: 4010kHz – 1500 to 2200 UTC.

Messages began on the hour in AM mode and were repeated on the half hour in single sideband (USB).


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Listings and Locations

DFC37 and DFD21 were both shown in the Guide to Utility Stations by Jörg Klingenfuss and in the Confidential Frequency List, compiled by Geoffrey Halligay.

The Klingenfuss Guide listed DFC37 and DFD21 as operated by the Deutsche Bundespost (the German Federal Post Office).

The Confidential Frequency List stated that DFC37 and DFD21 were part of an ‘internal net’ and placed the transmitter site at Frankfurt, West Germany.

E2K contributor Simon Mason, who has an excellent web site, asked Jörg Klingenfuss for more details and received this reply: “For several decades, nobody has ever succeeded in defining the exact location and the concrete purpose of these stations. Nobody has ever been able to contact such a station or to get a reception report. What people – especially SWLs from America – state and write about these stations are presumptions, guesses and plain nonsense. From our point of view, monitoring these stations is a waste of time and you get more from reading Bracknell Meteo teleprinter-coded weather for 24 hours, than from monitoring these number stations for 24 seconds. Consequently, we cannot answer your questions because Klingenfuss Publications considers giving facts and not guesses..."


The Fall of the Wall:

The Berlin Wall effectively ceased to exist in November 1989 and Germany finally unified in October 1990.

Under the Reunification Treaty, Russian Forces had to leave Germany by 31st August 1994.

All Allied Forces had until the end of December 1994 to leave.

The USSR ceased to exist on December 26, 1991.

Papa November, DFC 37 and DFD21 kept on transmitting until at least December 1992. The last log entry that I have for these stations is:

DFC 37: Call Sign: 816:85 Groups.

And I am merely a hobby radio user. How many more did they actually send? I guess it could have been a shopping list for Christmas, but I somehow doubt it!

On a more serious note, to whom were they still sending? The East German opposition had shut down. The Secret Service in West Germany (Bundesnachrichtendienst, BND) was starting to sift through the files of its East German counterpart, the Hauptverwaltung Aufklärung of the Ministerium für Staatssicherheit (the Ministry for State Security).

Maybe, someone was still keeping an eye on NATO forces, making sure the Russians and NATO both pulled out on time? However, given the recent concern shown by Angela Merkel surrounding US American (and other nations’) monitoring operations (her own mobile included) – and in the context of disclosures about the BND (and other German agencies) concerning their activities against the USA and others – perhaps more BND operators were in action at that time than we know about.

Who knows? It is what makes this such a great hobby!


Morse in Use Today

It is many years now since Britain, along with most of the rest of the radio world, including NATO forces, ceased to use Morse code as an everyday communications mode. However, Russia and China (The People’s Republic on the Chinese Mainland) still use it regularly.

China has several Morse code number stations, as does Russia.

Russia even uses it habitually for communications between multi-engined aircraft, as do the Russian Army’s naval and ground units. Paul (of our E2K group) remembers sending a telegram during his time in Guyana (British Guiana) and watching the operator send it, using Morse on a point-to-point link, while the rest of the world was using teleprinters.

Many number stations continue to use Morse code, as evidenced by the large list of stations with an ‘M’ Prefix.  I trust you can see where this is leading:

If sufficient people cease to know Morse, it becomes a code in its own right.

Personally, I am not now, and I never was, proficient in Morse: Guess who got sent QSF (“Quit Sending with your Feet”!) regularly…?

As I mentioned earlier, the only reason I worked in electronic warfare was my German language ability.

Later, there were no more special operators in the Royal Signals; those wizards who could receive at very high speeds. The basic standard, on first passing the trade test, was 30 words per minute. It was not unusual for them to receive at up to 40 or 50 wpm. As far as I am aware, the only branch of service to still routinely train Morse operators is the RAF.


Iraq and After

Come the first Iraq War (The Gulf War, codenamed Operation Desert Shield, 1990/1) and all this changed. It was suddenly realised that the Iraqi Armed Forces and others were routinely using Morse code. And, as you know, it is a totally different type of Morse alphabet. Worse, those sending it need not even understand Morse code; courtesy of the Racal MA-4231 Morse Decoder (Figs. 2 and 3).

Operators were now using keypads to send and receive Morse code. In addition to the Iraqi wireless capability, fibre optics were spread throughout the desert. This meant that interception was impossible without a hard tap.

The units and photos used here, by the way, are courtesy of Paul of E2K. Paul tells me the characters are Arabic, not Farsi. Having spent time in Aden, as I did, this is what Paul speaks.

You can imagine how well received we both were at Cardiff central bus station some years back greeting each other in Arabic only to be threatened by a local who accused us of mocking the Welsh language!


Project 858

The Iraqi al-Hadi Project, also called Project 858, referred to the agency responsible for SIGINT, ELINT and so on. During the first Iraq War, they interfered with allied communications, for which the MoD decided to train a percentage of operators in Morse. As a result, Croydon company Irwin-Desman Ltd. produced a training key (Fig. 4). Paul E2K was one of the design team working on it.

In addition to the Morse/Teleprinter capability at the embassy, Paul was surprised to see ‘Wavecom’ units installed; while there were no visible VHF/UHF antennas, the massive log-periodic aerial atop the roof would have been useful for HF on around 5 to 30MHz.

Operators were capable of RF powers to 1kW, and this may give us some idea of the radio communications apparatus used for diplomatic transmissions.

So, why mention all this? Before all the Iraqi ‘political posturing’, the crackdown on citizens and the subsequent removal of Saddam Hussein, at least one agent was busy in Iraq.

Conclusive proof of this came in the shape of a Farsi-language number station. One transmission was heard on 11116kHz at 1120UTC on 10th January 2003.

The activities in Iraq even prompted the much-respected author Frederick Forsyth to pen a novel entitled The Fist of God, in which the protagonist is clandestinely embedded in Iraq and receives instructions via an encrypted satellite device.

These kits replaced the short wave broadcast equipment of the Israeli MOSSAD some years back and the technology may well have replaced British and US number transmissions too.


Users of Morse Stations

As you may know, proficiency in Morse code is no longer a qualification requirement of the radio amateur examination. Nor is it in common use in the armed forces of the West. Indeed, save for some enthusiastic, and highly proficient, amateurs, it is not heard on amateur nets as often as in the earlier years.

However, there are number stations in Morse code to be captured and more stations than you might expect are still transmitting – of course, most traffic will be encrypted.

Two Chinese Number Stations, M89 and M95 have been active of late. Known frequencies for these are as follows: M89, on 3378; 270418 and 18142kHz and M95, on 4364kHz LSB.

Try using a WebSDR to receive them if you can, you may have be in luck.


Q Codes

Much use is made of Q codes, not just on the amateur bands. I apologise to the bulk of you, to whom all this is a statement of the blindingly obvious but here we go.

Rather than explaining ‘Q’ Codes here in detail, I recommend that you use your favourite search engine, download a list (available at many sites) and print it out to keep in the shack.

As you know, the code allows senders to use three letters starting with ‘Q’ and various other letters (never more than 3) to send messages and ask and reply to questions.

An example of this is the following: ‘QSL’ = I acknowledge receipt, and: QSL? = Can you acknowledge receipt? As you know, the interrogative at the end of QSL makes it into a question.

This applies to most trigrams in the Code. ‘De’ is ‘From’ and is followed by the sender’s callsign, usually at the end of the message. This allows contacts between people who may not even speak the same language, although, obviously, they have to know the ‘Q’ Code.

As you may know, ‘CQ’ (‘seek-you’) means ‘Calling All Stations’, ‘K’ is ‘Transmit’ or ‘Over’.

Finally, for a list of active number stations and their skeds, you should obtain an E2K Newsletter.

If (like me) you are not much use at Morse, you can use a software programme such as MixW4 or CWGet, v 2.37 by DXSoft to resolve it.

I use MixW, which decodes Morse, RTTY and many other modes.

I hope you have enjoyed this short series on the fascinating world of number stations, spies, the Cold War and secret voices. Get in touch if you like and check out ENIGMA2000.


Ed’s Reading Suggestions, see Parts One and Two of this series. More on East Germany is here: 


DDR: East German Spy Radios (Crypto Museum):

Fulbrook, M. (1995) Anatomy of a Dictatorship: Inside the GDR, 1949-1989 (Oxford University Press)

De La Motte, B. and Green, J. (2015) Stasi State or Socialist Paradise? The GDR and What Became of it (Artery Publications) 

Radio Listening in the GDR (Historical Resource):

Vreisleben, D. (2010) Spy Radio and Encryption Methods used by the MfS:


This article was featured in the July 2018 issue of Radio User