Bjørn Rørholt Bjørn Arnold Rørholt ( 27 August 1919 – 3 May 1993 ) was a Norwegian engineer , military officer , Secret Intelligence Service agent and resistance member during World War II . Early life . Rørholt was born in Aker as the son of military officer Arnold Rørholt ( 1884 – 1961 ) and his wife Luise Fredrikke Lund ( 1891 – 1965 ) . He was a first cousin of Vera Henriksen and a great - grandson of Friedrich Roscher . Rørholt finished his secondary education in 1937 , and enrolled at the Norwegian Institute of Technology in 1939 . After a short time he was drafted for compulsory military service . Not long after , when the Norwegian Military Academy opened for an extra influx of recruits , Rørholt enrolled there . World War II . When World War II reached Norway on 9 April 1940 , with the German invasion , the Military Academy cadet Rørholt helped fighting to repel the invaders . However , after the Norwegian Campaign Germany emerged victorious , and occupied Norway . After a short time as a prisoner - of - war , Rørholt returned to the Institute of Technology in autumn 1940 . In September 1940 the Secret Intelligence Service established two stations for radio communication ; the so - called Skylark A was led by Sverre Midtskau in Oslo while Skylark B was led by Erik Welle - Strand in Trondheim . Egil Reksten later took over for Welle - Strand . Skylark B established regular contact with the intelligence in London in 1941 , and helped spread messages about German troop and naval movements as well as vital information about German activity at Vemork heavy water plant . In September 1941 , however , Gestapo managed to track the Skylark B transmitting activity . Rørholt travelled to Oslo as a decoy , was nearly captured but escaped . His father was held hostage until November 1942 . Rørholt fled to Sweden via Iddefjord , accompanied by Knut Haukelid who had been involved in the Skylark A group in Oslo . Rørholt then travelled from Stockholm to Great Britain . Initially , he was withdrawn from active service because he might be known to the Germans . From 1942 the question of the German battleship " Tirpitz " became important . The presence of the ship in the Atlantic Ocean would be highly hazardous for the Allies ; thus the commanders wanted to track the ship ' s movements . A radio post named " Theta " was organized by Bjarne Thorsen , but the Allies wanted more . Rørholt returned to Norway in 1942 to operate the SIS radio station " Lerken " . Four radio transmitters were placed in the Trondheim area , one of them at the German - fortified Agdenes . Rørholt held a false identity as an insurance agent , and was thus allowed to travel freely with the alleged purpose of visiting customers . He was even escorted by the authorities from Agdenes to Trondheim . When " Tirpitz " was moved towards Northern Norway , " Lerken " was superseded by " Upsilon " and the network " Venus " . Einar Johansen was the central person here . The group of Norwegian resistance members that surveilled " Tirpitz " , referred to themselves as " Barnepikene " , " The Babysitters " . The radio post in Agdenes continued after the 1944 sinking of " Tirpitz " , and was operated by Magne Hassel . From November 1942 Rørholt was transferred to the department 4 ( FO IV ) of the Ministry of Defence , chairing the education of Norwegian radio agents in Great Britain . From 1944 to 1945 he participated in the liberation of Northern Norway , being one of the key figures on the Norwegian side together with Bernt Balchen . Also , the world - famous explorer Thor Heyerdahl was his second - in - command . Rørholt was awarded the War Cross with Sword and the Distinguished Service Order for his war contributions . Reportedly , he was the first Norwegian to receive the Distinguished Service Order . He was also a Commander of the Royal Norwegian Order of St . Olav . Later career . After the war Rørholt travelled to the United States . He had a position at the Norwegian Embassy in Washington DC , and later continued his engineering studies at the Harvard University , specializing in binary and communication technology . He started working for the Norwegian Armed Forces ( Sambandsregimentet ) in 1949 . He constructed the chiffer machine ETCRRM which was produced at Kjeller and used by NATO . In the military , he reached the rank of Colonel in 1958 . At that time he was the youngest Colonel in Norway , aged 39 . In 1985 he constructed a battery - driven , portable radar for blind people . The device , nicknamed " The Bat " , was based on ultrasound and mimicked the bat ' s sensory system . He wrote two memoir books from his World War II experiences , " Amatørspionen " Lerken " " ( " Amateur Spy ' The Lark ' " , 1985 ) and " Usynlige soldater " ( " Invisible Soldiers " , 1990 ) — the latter together with Bjarne Thorsen . He was married to Mia Sverdrup Thygeson from 1949 , and to Elsa Lundh from 1978 .