Stan Ames, G4OAV gave a talk about German spies active in the United Kingdom and the work involved in intercepting their communications to their handlers in Germany and attempts to turn them into double agents.
At the start of the war there was a “spy mania” with a poster campaign warning of the danger of careless talk. German agents were run by German Military Intelligence, the Abwehr, from near Hamburg. The Radio Security Services was established to try and intercept messages from the continent to German agents in the UK and to find the agents by direction finding. As well as intercept stations such as Hanslope Park equipped with HRO receivers individual listeners operated from their homes. Some of the members of the RSS were Radio Amateurs recruited through the RSGB. At the end of the war there were some 1200 listeners who listened in 2-3 hour spells to CW messages which included the Q code. Some of these intercepted messages were de-coded by Hugh Trevor-Roper without the aid of Bletchley Park.
One agent who was caught soon after landing by parachute near London Colney was Karl Richter. He was apprehended with £551 and US 1400 which he was to give to another German agent, known to the British as agent Tate. Richter was given the opportunity to become a double-agent but declined and was tried for treason and executed.
The first double-agent was a British battery salesman, known as agent Snow, who visited Germany before the war and was recruited by the Abwehr. On returning to Britain he told MI5 and became a double-agent, supplying identity cards to the Germans so they could be forged for use by German agents. These had subtle differences in the way the address was laid out that indicated to the British authorities that they were forged documents. The first radio message from the Abwehr to agent Snow was on 2 October 1939 requesting information on the disposition of RAF squadrons.
The most audacious double-agent was Juan Pajol, code name Garbo, who was recruited in Spain and flown to England. He managed to convince the Abwehr that he had a network of agents and supplied the Abwehr with many false reports of allied shipping movements.
Another double-agent was Eddie Chapman, code name Zigzag, who was a career criminal and was recruited by the Abwehr when he was released from prison in occupied Jersey. He was flown to England with the mission of sabotaging the de Havilland factory at Hatfield. Chapman was turned and the sabotage on the DH factory was faked to such an extent that an aerial reconnaissance flight convinced the Germans that the attack had been successful.
(report written by Owen, G0PHY for SADARS)
A WREN operates an HRO at Bletchley Park