(cf ground return
121History of the telephone — The history of the telephone chronicles the development of electrical technology that enabled bidirectional human speech conversations over distances farther than a person could shout.Telephone prehistoryMechanical devicesBefore the invention of… …
122MineCam — The MineCam is a remote exploration camera built by I.A.Recordings. It is used for mine shafts exploration and other similar environments. It was originally conceptualized in 1988, and since went under several design revisions. The name MineCam,… …
123Telegraphy — (from the Greek words (τηλε) = far and (γραφειν) = write) is the long distance transmission of written messages without physical transport of letters. Radiotelegraphy or wireless telegraphy transmits messages using radio. Telegraphy includes… …
124Simplex circuit — In telecommunication, the term simplex circuit has the following meanings: 1. A circuit that provides transmission in one direction only. 2. Deprecated definition: A circuit using ground return and affording communication in either direction, but …
125San Diego Electric Railway — Infobox SG rail railroad name=San Diego Electric Railway logo filename=SDERy logo.png logo size=200 marks=SDER locale=California start year=1892 end year=1949 old gauge= hq city=San Diego, CaliforniaThe San Diego Electric Railway (SDERy) was a… …
126John Renshaw Carson — (June 28, 1886 October 31, 1940), who published as J. R. Carson, was a noted transmission theorist for early communications systems. He invented single sideband modulation.Carson was born in Pittsburgh, Pennsylvania, graduated from Princeton… …
127Army Security Agency — Die United States Army Security Agency (ASA) war ein ELINT Geheimdienst der US Army zwischen 1945 und 1977. Ihr Motto war Vigilant Always (Immer wachsam). Die Agentur war der Nachfolger mehrerer Nachrichtendienstoperationen der US Army während… …
128United States Army Security Agency — ASA Staatliche Ebene Bund Stellung der Behörde Signals Intelligence Gründung 1945 Hauptsitz Arlington …
