Great Seal Bug
26 MAY 1960
GREAT SEAL BUG
On 4 August 1945, as WWII ended, a Moscow school children’s group, the Young Pioneers, presented US Ambassador W. Averell Harriman with a gift of friendship–a 2-foot carved wooden likeness of the Great Seal of the United States. It was hung on the wall of the Ambassador’s office in Spaso House, his residence in Moscow. No one in the next seven years noticed the barely visible pin holes under the eagle’s beak.
The ensuing Cold War cooled East-West relations and prompted superpower eavesdropping. But periodic debugging sweeps of our Moscow facilities revealed nothing of concern. Then in early 1951, a British technician scanning signals with a broadband FM radio was shocked to hear the voice of (then) Ambassador George F. Kennan coming from his radio! At that moment Kennan was conducting a meeting in his Spaso House office. For several months technicians combed the office in vain for the listening device, finally concluding that it was only active at intervals. They asked Kennan to stage a sham meeting one evening in September 1951 during which he dictated a false document to his secretary. The trick worked, the device activated and led technicians to the Great Seal carving. Examination revealed a hidden cavity behind the eagle containing a small resonating box attached to a 9-inch metal rod. Curiously, the device had no batteries, wires, or apparent power source.
“The Thing” was the invention of Russian physicist Lev Sergeyevich Termen, known in the US as Léon Theremin. It used the same induced capacitance principles as the Theremin musical synthesizer that emits other-worldly tones used in the 1966 Beach Boys hit, “Good Vibrations.” Sound waves from the room caused minute movements in the resonating diaphragm, which induced changes in a capacitor plate at the end of the rod. These generated no signal of their own, but when a 330MHz beam was directed at the device from outside, the reflected wave was modulated by the capacitance changes. Using a device like an ordinary FM radio, these modulations could be translated back into sound. Emitting no radiation of its own, the device was undetectable with contemporary de-bugging equipment and could have operated indefinitely.
The discovery of the Great Seal bug was kept secret until this day. An American U-2 spy plane had been shot down over Russia, and the Soviets had called a special session of the UN Security Council in protest. On this fourth day of that session our Ambassador to the UN, Henry Cabot Lodge, Jr., produced the Great Seal bug as evidence the Soviets too, were guilty of espionage. In the years since 1952, over 100 similar devices had been recovered from diplomatic missions throughout Eastern Europe.
Watch for more “Today in Naval History” 30 MAY 23
CAPT James Bloom, Ret.
Ginsky, Albert. Theremin: Ether Music and Espionage. Champaign, IL: Univ. of Illinois Press, 2000.
Kennan, George F. Memoirs, 1950-1963. New York, NY: Pantheon, 1983.
Murray, Kevin D. “The Great Seal Bug, Parts I, II, III.” Murray Associates website, AT: http://www.spybusters.com/great_seal_bug_part_I.html, retrieved 5 May 2014.
National Security Administration (NSA Whitepaper). The Gunman Project: Learning from the Enemy. Los Gatos, CA: Progressive Management (digital book), 2014.
ADDITIONAL NOTES: The U-2 shot down on 1 May 1960 was that of CIA pilot Francis Gary Powers. He was overflying the heart of Russia from Pakistan to Scandinavia at 70,000 feet—thought to be beyond the range of Soviet surface-to-air missiles. Powers was captured and tried in a Soviet court, resulting in a conviction for espionage. He was sentenced to three years in prison and seven years of hard labor and was ultimately exchanged in a prisoner swap, 10 February 1962.
