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Article: 'Y' stations

During the Second World War the British developed a network of listening stations (called Y Stations) throughout the United Kingdom. Two such stations existed in Northern Ireland – one at Ramore Head, Portrush and the other at Gilnahirk in east Belfast. The purpose of these stations was to listen in to the communications being transmitted by the Germans, record the messages and then send them to a special team of experts as quickly as possible.

Naturally the Germans transmitted their messages in code and to do that they used a device known as an Enigma Machine. This machine consisted of three revolving ‘wheels’ or ‘rotors’ that could be taken out and changed around and another section called the ‘plugboard.’ This section had several cables with a plug at each end that could be used to plug pairs of letters together. If A were plugged to B then, on typing the letter A, the electric current would follow the path that was normally associated with the letter B, and vice versa. By changing the rotors and their position within the Enigma Machine as well as the combination of pairs of letters then the total number of possible ways in which a standard Enigma Machine could be set up was approximately 158 million million million.

Even though the Allies had managed to capture Enigma Machines they really needed to know the daily German key being used which was changed at midnight every night. German Enigma Machine operators were issued with a Key Sheet every month, which told them how to set up their Enigma Machines for every day of that month. If the Allies recovered a Key Sheet then they would be able to read the Enigma messages.

Consequently Key Sheets were closely guarded and were printed in soluble ink. If it ever looked as though a Key Sheet might be captured by the Allies, then the German soldiers would dip it in water to destroy the information. The Germans believed that as long as the Allies did not obtain a Key Sheet then the sheer volume of possible settings would make it impossible for anyone to break the code being used.

The task of breaking the German code was given to an organisation called the Government Code and Cipher School, now known as GCHQ - Government Communications Headquarters. The original school was set up in 1939 at Bletchley Park in Buckinghamshire and the work carried out at Bletchley Park was one of the most guarded secrets of the war.
The people recruited to work there came from a variety of backgrounds. There were experienced code breakers, secret service officers, mathematicians, scientists, crossword experts, international chess players, students, actresses and even astrologers and debutants. Some 9,000 people were working at Bletchley Park at the height of the code breaking efforts in January 1945 and over 10,000 worked there at some point during the war.

The code breakers worked in shifts around the clock for the whole of the war, using paper and pencil as well as newly invented mechanical techniques to work out the particular Enigma machine settings for each and every single day. Unwittingly, the Germans themselves helped the British to decipher the Enigma. For example:

• Messages often began with the same opening text - many began with the word Spruchnummer (Message Number), and many Air Force messages began with the phrase An die Gruppe (To the Group).
• Messages often enciphered routine information such as weather reports and phrases such as Keinebesondere Ereignisse (nothing to report).
• Messages often ended with Heil Hitler!
• The Germans often transmitted the same message more than once with each version enciphered differently.

Today, historians believe that the work of the code breakers at Bletchley Park shortened the war by two years. There are at least 3 Bletchley Park war veterans currently living in Northern Ireland.

However the raw data needed to allow the brilliant minds at Bletchley Park crack the German codes was provided by the men and women who spent hours and hours listening in on the Germans and accurately recording those messages. Those who worked at the Y Stations at Ramore Head and Gilnahirk played their part, doing tasks which may have been monotonous at times but ever so important.

Angela Neilly served in the WRNS and spent a few months at the Y Station in Portrush. She remembers the very steep path up to the Station which acted as a Coastguard centre as well. Her job was to receive and send messages in plain text using either a teleprinter or telephone. ‘Messages in code,’ she says ‘were given to the ‘Almighty Ones’ who were anyone with a stripe.’ She recalls that the building wasn’t very big and that the sailors had a leisure room of their own, the coastguards their own office and the largest office was used by a team of 4 WRNS.

The Y Station at Gilnahirk was situated near the junction of Manns Road and the Braniel Road. A local Second World War veteran worked at the site just after the war after spending some time as a trainer at Bletchley Park. He recalls that about 120 people worked on the site. The Station consisted of one main building, an administration building and a hut. He remembers that the DF (Directional Finding) equipment was ‘the only thing visible.’ He refuses to say anything about the secret work undertaken because all who worked in such establishments had signed the Official Secrets Act.

Article kindly supplied by Richard Parkinson.