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The operators would move the semaphore arms to successive positions to spell out text messages in semaphore code, and the people in the next tower would read them. An optical telegraph is a line of stations, typically towers, for the purpose of conveying textual information by means of visual signals (a form of optical communication).
The shape of the trafficator arm is closely based upon the shape of the semaphore signal arm used by the Royal Bavarian State Railways beginning in 1890. The shape differs in that the trafficator has only the lower 'blade' of the rail signal's terminal 'arrowhead', so that the retracted trafficator sits flush with the vehicle's exterior.
Semaphore (lit. ' apparatus for signalling '; from Ancient Greek σῆμα (sêma) 'mark, sign, token' and Greek -φόρος (-phóros) 'bearer, carrier') [1] is the use of an apparatus to create a visual signal transmitted over distance. [2] [3] A semaphore can be performed with devices including: fire, lights, flags, sunlight, and moving arms.
A replica of a Chappe telegraph tower (18th century). A 'semaphore telegraph', also called a 'semaphore line', 'optical telegraph', 'shutter telegraph chain', 'Chappe telegraph', or 'Napoleonic semaphore', is a system used for conveying information by means of visual signals, using towers with pivoting arms or shutters, also known as blades or paddles.
The earliest electronic systems available as factory installations were vacuum tube car radios, starting in the early 1930s.The development of semiconductors after World War II greatly expanded the use of electronics in automobiles, with solid-state diodes making the automotive alternator the standard after about 1960, and the first transistorized ignition systems appearing in 1963.
The International Code of Signals (INTERCO) is an international system of signals and codes for use by vessels to communicate important messages regarding safety of navigation and related matters. Signals can be sent by flaghoist , signal lamp ("blinker"), flag semaphore , radiotelegraphy, and radiotelephony.
The Chappe telegraph was a French semaphore telegraph system invented by Claude Chappe in the early 1790s. The system was composed of towers placed every 5 to 15 kilometers. Coded messages were sent from tower to tower, with transmission being handled by tower operators using specially designed telescopes.
Signal cabins coordinated signals that indicated whether or not a section of track was clear of other traffic. Early signals were mechanical, while later signals were operated electrically. The most common form of mechanical signal was the semaphore signal. These consisted of a metal framed tower with one or more arms that could be inclined at ...