File:Detector magnetico Marconi 1902 - Museo scienza e tecnologia Milano.jpg
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Summary
| Description |
Italiano: Detector magnetico Marconi utilizzato nella campagna sperimentale a bordo della Carlo Alberto nell'estate del 1902. Esposto al Museo nazionale della scienza e della tecnologia Leonardo da Vinci di Milano.
English: One of the earliest prototype magnetic detectors, built by inventor Guglielmo Marconi and used in his wireless experiments on board the ship Carlo Alberto in the summer of 1902. The magnetic detector was a primitive radio wave detector used in the first wireless telegraphy radio receivers from its invention in 1902 to about 1915, when it was replaced by vacuum tubes. An endless band of iron wires (apparently missing from this device) was rotated around the two pulleys. driven by a windup clockwork mechanism in the box. The wires passed through a coil attached to the antenna, in the magnetic field produced by the two horseshoe magnets (center). When a radio wave from the antenna passed through the coil, it's oscillating magnetic field overcame the hysteresis of the iron wires, magnetizing them. This produced a pulse of current in a second coil around the wires, attached to an earphone. The signals produced by the early spark gap transmitters consisted of pulses of damped radio waves, repeating at an audio rate, so in the earphone the received signal sounded like musical beeps. Text messages were transmitted in the sequence of beeps by Morse code, which the operator decoded. Exhibited at National Museum of Science and Technology Leonardo da Vinci in Milan, Italy. |
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| Author | Alessandro Nassiri for Museo nazionale scienza e tecnologia L. da Vinci | |||||||||||||||||||||||
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 20:17, 25 April 2016 | | 1,980 × 1,320 (566 KB) | Marco Chemello (Museoscienza) | User created page with UploadWizard |
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