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- Crystal_radio abstract "A crystal radio receiver, also called a crystal set or cat's whisker receiver, is a very simple radio receiver, popular in the early days of radio. It needs no battery or power source and runs on the power received from radio waves by a long wire antenna. It gets its name from its most important component, known as a crystal detector, originally made with a piece of crystalline mineral such as galena. This component is now called a diode.Crystal radios are the simplest type of radio receiver and can be handmade with a few inexpensive parts, like an antenna wire, tuning coil of copper wire, capacitor, crystal detector and earphones. They are distinct from ordinary radios because they are passive receivers, while other radios use a separate source of electric power such as a battery or the mains power to amplify the weak radio signal from the antenna so it is louder. Thus crystal sets produce rather weak sound and must be listened to with sensitive earphones, and can only pick up stations within a limited range.The rectifying property of crystals was discovered in 1874 by Karl Ferdinand Braun, and crystal detectors were developed and applied to radio receivers in 1904 by Jagadish Chandra Bose, G. W. Pickard and others. Crystal radios were the first widely used type of radio receiver, and the main type used during the wireless telegraphy era. Sold and homemade by the millions, the inexpensive and reliable crystal radio was a major driving force in the introduction of radio to the public, contributing to the development of radio as an entertainment medium around 1920.After about 1920, crystal sets were superseded by the first amplifying receivers, which used vacuum tubes (Audions), and became obsolete for commercial use. However they continued to be built by hobbyists, youth groups and the Boy Scouts as a way of learning about the technology of radio. Today they are still sold as educational devices, and there are groups of enthusiasts devoted to their construction who hold competitions comparing the performance of their home-built designs.Crystal radios can be designed to receive almost any radio frequency band, but most receive the AM broadcast band. A few receive the 49-meter international shortwave band, but strong signals are required. By the nature of their operation, crystal radios can only demodulate amplitude modulation (AM) signals, and not frequency modulation (FM) or digital signals. The first crystal sets received wireless telegraphy signals broadcast by spark-gap transmitters at frequencies as low as 20 kHz.".
- Crystal_radio thumbnail Crystal_radio_enthusiast.JPG?width=300.
- Crystal_radio wikiPageExternalLink books?id=4IDLK8NMDBQC.
- Crystal_radio wikiPageExternalLink books?id=DzcMK-2mFQUC.
- Crystal_radio wikiPageExternalLink books?id=MZTaMdOH7VIC.
- Crystal_radio wikiPageExternalLink books?id=TK-7a_BjUCwC.
- Crystal_radio wikiPageExternalLink books?id=k8Wpg2wxDLcC.
- Crystal_radio wikiPageExternalLink xtal.htm.
- Crystal_radio wikiPageExternalLink cristadyne.html.
- Crystal_radio wikiPageExternalLink www.bentongue.com.
- Crystal_radio wikiPageExternalLink crystalradio.htm.
- Crystal_radio wikiPageExternalLink znrfamp2-el.htm.
- Crystal_radio wikiPageExternalLink www.vcomp.co.uk.
- Crystal_radio wikiPageID "232249".
- Crystal_radio wikiPageRevisionID "605056778".
- Crystal_radio align "center".
- Crystal_radio caption "Australian signallers using a Marconi Mk III crystal receiver, 1916.".
- Crystal_radio caption "Crystal radio, Germany, ca. 1924".
- Crystal_radio caption "German Heliogen brand radio showing "basket-weave" coil, 1935".
- Crystal_radio caption "Homemade "loose coupler" set , Florida, ca. 1920".
- Crystal_radio caption "Marconi Type 103 crystal set.".
- Crystal_radio caption "Marconi Type 106 crystal receiver used for transatlantic communication, ca. 1921".
- Crystal_radio caption "Polish Detefon brand radio, 1930-1939, using a "cartridge" type crystal".
- Crystal_radio caption "SCR-54A crystal set used by US Signal Corps in World War I".
- Crystal_radio caption "Soldier listening to a crystal radio during World War I, 1914".
- Crystal_radio caption "Swedish "box" crystal radio with earphones, ca. 1925".
- Crystal_radio footer "During the wireless telegraphy era before 1920, crystal receivers were "state of the art", and sophisticated models were produced. After 1920 crystal sets became the cheap alternative to vacuum tube radios, used in emergencies and by youth and the poor.".
- Crystal_radio hasPhotoCollection Crystal_radio.
- Crystal_radio image "Australian signallers 1916.jpg".
- Crystal_radio image "D 1925 Jahnke Schiebspulendetektor.jpg".
- Crystal_radio image "Heliogen medium wave galena radio.JPG".
- Crystal_radio image "Kristallmottagare.JPG".
- Crystal_radio image "Marconi Type 106 crystal radio receiver.jpg".
- Crystal_radio image "Marconi crystal radio receiver.jpg".
- Crystal_radio image "PensacolaAug081920sCrystalRadioKodak.jpg".
- Crystal_radio image "RX 1914 tranchée .JPG".
- Crystal_radio image "Radio detefon 1.jpg".
- Crystal_radio image "Signal Corps SCR-54A crystal radio.jpg".
- Crystal_radio width "85".
- Crystal_radio subject Category:Amateur_radio_receivers.
- Crystal_radio subject Category:Electronic_design.
- Crystal_radio subject Category:History_of_radio.
- Crystal_radio subject Category:Radio_electronics.
- Crystal_radio subject Category:Receiver_(radio).
- Crystal_radio subject Category:Types_of_radios.
- Crystal_radio type AmateurRadioReceivers.
- Crystal_radio type Artifact100021939.
- Crystal_radio type ElectronicEquipment103278248.
- Crystal_radio type Equipment103294048.
- Crystal_radio type Instrumentality103575240.
- Crystal_radio type Object100002684.
- Crystal_radio type PhysicalEntity100001930.
- Crystal_radio type RadioReceiver104043733.
- Crystal_radio type Receiver104060647.
- Crystal_radio type Set104176528.
- Crystal_radio type Whole100003553.
- Crystal_radio comment "A crystal radio receiver, also called a crystal set or cat's whisker receiver, is a very simple radio receiver, popular in the early days of radio. It needs no battery or power source and runs on the power received from radio waves by a long wire antenna. It gets its name from its most important component, known as a crystal detector, originally made with a piece of crystalline mineral such as galena.".
- Crystal_radio label "Crystal radio".
- Crystal_radio label "Detektorempfänger".
- Crystal_radio label "Kristalontvanger".
- Crystal_radio label "Radio a galena".
- Crystal_radio label "Radio a galena".
- Crystal_radio label "Rádio de galena".
- Crystal_radio label "Récepteur à cristal".
- Crystal_radio label "Детекторный приёмник".
- Crystal_radio label "矿石收音机".
- Crystal_radio label "鉱石ラジオ".
- Crystal_radio sameAs Krystalka.
- Crystal_radio sameAs Detektorempfänger.
- Crystal_radio sameAs Radio_a_galena.
- Crystal_radio sameAs Récepteur_à_cristal.
- Crystal_radio sameAs Radio_a_galena.
- Crystal_radio sameAs 鉱石ラジオ.
- Crystal_radio sameAs 광석_라디오.
- Crystal_radio sameAs Kristalontvanger.
- Crystal_radio sameAs Rádio_de_galena.
- Crystal_radio sameAs m.01hs73.
- Crystal_radio sameAs Q695140.
- Crystal_radio sameAs Q695140.
- Crystal_radio sameAs Crystal_radio.
- Crystal_radio wasDerivedFrom Crystal_radio?oldid=605056778.
- Crystal_radio depiction Crystal_radio_enthusiast.JPG.
- Crystal_radio isPrimaryTopicOf Crystal_radio.