The Thing: Cold War Innovation in Hidden Surveillance

During the Cold War, Soviet intelligence created an ingenious surveillance device known as "The Thing" - a passive cavity resonator hidden inside a wooden Great Seal of the United States gifted to the U.S. Ambassador in Moscow in 1945. Unlike conventional microphones that require power sources, this device, designed by Léon Theremin, operated passively. When targeted by a specific radio beam from nearby Soviet operatives, its thin membrane would vibrate in response to sound waves from conversations, modulating and reflecting the signal with the audio information. The technology remained undetected for seven years, until 1952, baffling American experts with its elegant simplicity and the absence of a power source or active components. Over 130 similar devices were eventually found in U.S. diplomatic facilities across the Eastern Bloc. This technological breakthrough fundamentally changed counterintelligence practices, leading to the development of secure rooms (SCIFs) and comprehensive security protocols that continue to evolve today as the principles behind these passive listening devices remain relevant to modern security concerns.

https://www.ihadnoclue.com/article/1125356897723875329