Search results
Results from the WOW.Com Content Network
The usual waveform of alternating current in most electric power circuits is a sine wave, whose positive half-period corresponds with positive direction of the current and vice versa (the full period is called a cycle). "Alternating current" most commonly refers to power distribution, but a wide range of other applications are technically ...
The arc converter, sometimes called the arc transmitter, or Poulsen arc after Danish engineer Valdemar Poulsen who invented it in 1903, [1] [2] was a variety of spark transmitter used in early wireless telegraphy. The arc converter used an electric arc to convert direct current electricity into radio frequency alternating current.
An electric arc between two nails. An electric arc (or arc discharge) is an electrical breakdown of a gas that produces a prolonged electrical discharge. The current through a normally nonconductive medium such as air produces a plasma, which may produce visible light. An arc discharge is initiated either by thermionic emission or by field ...
A frequency changer or frequency converter is an electronic or electromechanical device that converts alternating current of one frequency to alternating current of another frequency. The device may also change the voltage , but if it does, that is incidental to its principal purpose, since voltage conversion of alternating current is much ...
Invented by Peter Cooper Hewitt in 1902, it was used to convert alternating current (AC) into direct current (DC). From the 1920s on, research continued on applying thyratrons and grid-controlled mercury arc valves to power transmission.
A sketch of the Pearl Street Station. In 1881, two electricians built the world's first power system at Godalming in England. It was powered by two water wheels and produced an alternating current that in turn supplied seven Siemens arc lamps at 250 volts and 34 incandescent lamps at 40 volts. [1]
Mercury rectifier on display in the Beromünster AM transmitter in Switzerland, before being decommissioned.Three-phase full-wave rectifier with six anodes. A mercury-arc valve or mercury-vapor rectifier or (UK) mercury-arc rectifier [1] [2] is a type of electrical rectifier used for converting high-voltage or high-current alternating current (AC) into direct current (DC).
His experiments with alternating current arc lighting at South Foreland Lighthouse in 1857-60 [6] were the subject of a lecture by Michael Faraday at the Royal Institution. [7] One of Holmes' generators built in 1867 and used at Souter Lighthouse is displayed at the Science Museum, London.