manual telegraphy
1Telegraph key — A straight key style of telegraph key J38 World War II era U.S. military model …
2Relay league — A relay league is a chain of message forwarding stations in a system of optical telegraphs, radio telegraph stations, or riding couriers.An interesting description of these early 19th century methods and its evolution into the electrical… …
3Invention of radio — Great Radio Controversy redirects here. For the album by the band Tesla, see The Great Radio Controversy. Contents 1 Physics of wireless signalling 2 Theory of electromagnetism …
4telegraph — telegrapher /teuh leg reuh feuhr/; esp. Brit., telegraphist, n. /tel i graf , grahf /, n. 1. an apparatus, system, or process for transmitting messages or signals to a distant place, esp. by means of an electric device consisting essentially of a …
5Morse code — Chart of the Morse code letters and numerals Morse code is a method of transmitting textual information as a series of on off tones, lights, or clicks that can …
6Telephone switchboard — PBX switchboard, 1975 A switchboard (also called a manual exchange) was a device used to connect a group of telephones manually to one another or to an outside connection, within and between telephone exchanges or private branch exchanges (PBXs) …
7Telephone exchange — A telephone operator manually connecting calls with cord pairs at a telephone switchboard. In the field of telecommunications, a telephone exchange or telephone switch is a system of electronic components that connects telephone calls. A central… …
8Signal Corps in the American Civil War — U.S. Army Signal Corps station on Elk Mountain, Maryland, overlooking the Antietam battlefield. The Signal Corps in the American Civil War comprised two organizations: the U.S. Army Signal Corps, which began with the appointment of Major Albert J …
9Cryptanalysis of the Lorenz cipher — The Lorenz SZ machines had 12 wheels each with a different number of cams (or pins). Wheel number 1 2 3 4 5 6 7 …
10List of writing systems — This is a list of writing systems (or scripts), classified according to some common distinguishing features.The usual name of the script is given first (and bolded); the name of the language(s) in which the script is written follows (in brackets) …
