About: Crystal radio

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Simple radio receiver circuit used mostly for AM reception

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  • simple radio receiver circuit used mostly for AM reception (en)
  • receptor de radio (es)
  • tipologia di ricevitore radio (it)
  • yksinkertainen radiovastaanotin (fi)
  • récepteur radio à cristal modulation d'amplitude fonctionnant sans alimentation électrique (fr)
  • historisches Gerät zum Empfang von Hörfunksendungen in den Anfangstagen des Rundfunks (de)
  • Опростена схема на радиоприемник за преобразуване на радиовълните в звуков сигнал. (bg)
  • 收音机类型 (zh)
  • radijski sprejemnik s kristalno amplitudno modulacijo, ki deluje brez napajanja (sl)
  • простейший тип радиоприёмника (ru)
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  • right (en)
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  • 0001-08-30 (xsd:gMonthDay)
  • Bose's millimeter wave spectrometer, 1897. The spark transmitter is inside the box '. The galena detector is inside the horn antenna ' with a thumbscrew ' which adjusted the pressure of a metal point against the crystal. The battery ' creates a current through the detector measured by the galvanometer (en)
  • Bose's galena detector from his 1901 patent. This version was deliberately made to look and function like a human eyeball, with a lens focusing millimeter waves on the galena contact. (en)
  • "Microphone" coherer detector from 1909 similar to one Pickard discovered rectification with, widely used in the first receivers. It consists of a steel needle resting on two carbon blocks. A semiconducting layer of corrosion on the steel may have been responsible for the rectification. (en)
dbp:date
  • May 2016 (en)
dbp:direction
  • horizontal (en)
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  • "Two slider" crystal radio circuit. and example from 1920s. The two sliding contacts on the coil allowed the impedance of the radio to be adjusted to match the antenna as the radio was tuned, resulting in stronger reception. The capacitance which created the tuned circuit was provided by the parasitic capacitance of the coil, and the antenna. (en)
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  • Crystal radio.agr.jpg (en)
  • GWP-836531Patent.png (en)
  • Jagadish Chandra Bose microwave apparatus.png (en)
  • Microphone wireless detector 1909.png (en)
  • Two slider crystal radio circuit.svg (en)
  • US Patent 755840-Jagadish Chandra Bose-Detector for electrical disturbances fig 1-3.png (en)
dbp:reason
  • Campbell only says demodulation requires a nonlinear element; Campbell talkes about the "envelope" of a vacuum tube. (en)
  • Williams p 22 assumes the voltage is an absurd 7 V. (en)
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  • The frying ceased, and the signals, though much weakened, became materially clearer through being freed of their background of microphonic noise. Glancing over at my circuit, I discovered to my great surprise that instead of cutting out two of the cells I had cut out all three; so, therefore, the telephone diaphragm was being operated solely by the energy of the receiver signals. A contact detector operating without local battery seemed so contrary to all my previous experience that ... I resolved at once to thoroughly investigate the phenomenon. (en)
  • Such variability, bordering on what seemed the mystical, plagued the early history of crystal detectors and caused many of the vacuum tube experts of a later generation to regard the art of crystal rectification as being close to disreputable. (en)
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  • 150 (xsd:integer)
  • 178 (xsd:integer)
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  • 350 (xsd:integer)
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  • Crystal radio (en)
  • مستقبل راديو بلوري (ar)
  • Ràdio de galena (ca)
  • Krystalka (cs)
  • Kristalricevilo (eo)
  • Radio de galena (es)
  • Detektorempfänger (de)
  • Récepteur à cristal (fr)
  • 鉱石ラジオ (ja)
  • Radio a galena (it)
  • 광석 라디오 (ko)
  • Kristalontvanger (nl)
  • Rádio de galena (pt)
  • Детекторный приёмник (ru)
  • Kristallmottagare (sv)
  • Детекторний приймач (uk)
  • 矿石收音机 (zh)
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