BBC NEWS | UK | Wales | Codebreaker's sleep-talk worries A World War II codebreaker has told how she was so afraid of giving away secrets by talking in her sleep that she was worried about going to bed. Mair Eluned Russell-Jones, 92, worked from 1942 at Bletchley Park, a site whose role in decrypting German signals was only revealed decades later. She has now been honoured by Prime Minister Gordon Brown for her efforts at the Buckinghamshire mansion. She feared her landlord was listening at her door and even fell ill. She has now joined a number of men and women to have been publicly recognised after working at the confidential site, known as Station X. Many historians agree that the codebreakers' efforts shortened the war by two years. Mair Eluned Russell-Jones, pictured in her early 20s Their success allowed the Allies to know in advance what German forces were planning. About 10,000 people worked on breaking codes during the war, and about 1,500 are still alive. Welsh-speaking Mrs Russell-Jones, from Caerphilly, has received the Government Code and Cipher School certificate signed by the prime minister, and a commemorative badge. She said: "We were sworn to secrecy and the landlord seemed very interested in what we were doing. "I thought maybe he was listening at the door in case we talked in our sleep. I was afraid to go to sleep and became ill as a result." Cramped hut Her role at Bletchley Park saw her with about 20 other women in a small, cramped hut where she sat in front of a machine and decrypted the German code coming in. She said: "There were letters in groups of five and we had to try and sort them out, which did not happen very often. "We didn't break the code though, the people above us did, and there were not that many who could do it. "We had to translate it from German and eventually it got to whoever it was meant for but none of us understood what we were seeing." Bletchley Park's contribution to the war effort has become publicly recognised She added: "I remember mostly being bored - it was really, really boring just sitting there watching the letters coming through and trying to sort it out. "However, when a code was broken it was so exciting, but it only happened about once a week. "Everybody shouted with joy but then it had to go to the officers in the Army, Navy and Air Force and it was serious then, but we were pleased we had got the cipher broken and the people it was going to knew what they were fighting." Mrs Russell-Jones, who has five children, 15 grandchildren and one great-grandchild, was a student when a friend of hers suggested she apply for a job with the Foreign Office. She was one of more than 1,500 Bletchley Park veterans to receive the commemorative badge and a certificate, expressing thanks for her contribution to the war effort. Speaking of the award, Mrs Russell-Jones, who has been married to the Rev Thomas Russell-Jones, 91, for 63 years, said: "I am thrilled. It has made me think back to the war, not that I haven't thought of it before. "When I was there I really felt I was making a contribution to the war effort. It was all worth it."