amplifier. The devices were developed under the Easy Chair research contract and were known as Easy Chair Mark I (1955), Mark II (1956), Mark III (1958), Mark IV (1961) and Mark V (1962). Although initially they could not get the resonant cavity microphone to work reliably, several products involving passive elements (PEs) were developed for the CIA as a result of the research. In 1965, the NRP finally got a reliably working pulsed cavity resonator, but by that time the CIA was no longer interested in passive devices, largely because of the high levels of RF energy involved. In May 1960, The Thing was mentioned on the fourth day of meetings in the United Nations Security Council, convened by the Soviet Union over the 1960 U-2 incident where a U.S. spy plane had entered their territory and been shot down. The U.S. ambassador Henry Cabot Lodge Jr. showed off the bugging device in the Great Seal to illustrate that spying incidents between the two nations were mutual and to allege that Nikita Khrushchev had magnified this particular incident as a pretext to abort the 1960 Paris Summit: "I produced a wooden carving of the Great Seal of the United States which was given by some Russians to the United States Ambassador to the Soviet Union and which hung in his office behind his desk, and which contained an electronic device which made it possible for persons on the outside possessing a certain type of technical device to hear everything that went on. I produced that as a piece of evidence, and it is direct, fresh, authentic evidence, to show the effectiveness and the thoroughness of Soviet espionage." See also Moscow Signal Nonlinear junction detector Laser microphone Ragemaster, radar-powered video-cable tap and retransmitter Surveillance Telstar Mechta, soccer ball given as a diplomatic gift to President Trump by Vladimir Putin that incited fears of a similar listening device TEMPEST Trojan Horse Notes References External links Passive Resonant Cavity & "Spycatcher" Technical Surveillance Devices The Great Seal Bug Story, Spybusters, Kevin D. Murray A Trojan Seal – Security Management, Ken Stanley, April 2010 History of the Bureau of Diplomatic Security of the United States Department of State, October 2011, pp. 136–137 How the Soviet Union spied on the US embassy for 7 years, Hackaday, Adam Fabio, December 2015 Covert listening devices Espionage Espionage devices Espionage techniques KGB Inventions by Léon Theremin Soviet Union–United