were also sent in Morse code, but were either prearranged code signals or were encrypted. Rendered obsolete by satellite technology and the end of the cold war, NSS ceased operation and all of the antennas and most of the towers were demolished in 1999. Three of the smaller 600-foot towers were preserved near the tip of Greenbury Point to serve as aids to navigation for boaters on the Chesapeake Bay. The callsign, operating from Annapolis, was brought back for the May 8, 2021 Armed Forces Day radio test. This is an annual event when amateur radio operators can work through crossband communications with certain military stations. However the station was active for only 16 hours. References External links Communications and electronic installations of the United States Navy Buildings and structures in Anne Arundel County, Maryland Towers in Maryland Military radio systems Military installations closed in 1999 Communications in Maryland 1918 establishments in Maryland Closed installations of the United States Navy