Definition of "listening post" []

• A facility established to monitor radio and microwave signals and analyse their content to secure information and intelligence for use by the security and diplomatic community and others. (noun)

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• "The German listening post in Sinyavino heard the Russian tank commanders call:"
• "In the next few hours the Cray supercomputers at the NRO/NSA listening post in Menwith Hill, England, would flag an anomalous sequence in one of the Arctic's hydrophones, decipher the pounding as an SOS, triangulate the coordinates, and dispatch a rescue plane from Thule Air Force Base in Greenland."