Diodemodtager

En krystalmodtagere (også kendt som et krystalapparat eller en krystalradio) blev først bygget omkring 1900 af Greenleaf Whittier Pickard.^[1] Krystalmodtagerne anvendte krystaldetektordioder til at detektere radiofonisignaler. Andre ensrettende overgange blev lavet af oxiderede metallegeringer.

Den "moderne" udgave af krystalmodtageren er en diodemodtager, hvor krystallet er udskiftet med en småsignal Schottky-diode baseret på halvledermaterialet silicium eller en punktkontaktdiode baseret på halvledermaterialet germanium.

En krystalmodtager eller diodemodtager skal ikke have elektricitet fra batteri eller elnet - det man hører i hovedtelefonen eller krystaløreproppen fås alene fra de modtagne radiobølger.

^ G. W. Pickard, "How I Invented the Crystal Detector". Electrical Experimenter, vol. VII, no. 4, p. 325, Aug. 1919 Citat: "...In 1898, when my work in Radio-communication began, there was but one detector—the coherer...In the period 1902 to 1906, I tested many different minerals and combinations, including magnetite, pyrite, galena, molybdenite, silicon and zincite. Much development was also required on holders for these minerals...31,250 Crystal Detectors Invented. A list of the several thousand materials I have tested would make dry reading. Suffice it to say that I have found some tzvo hundred and fifty minerals and furnace products which make operative detectors, cither against metallic contacts, or in combination with other minerals. The possible combinations of these two hundred and fifty substances amounting to some 31,250, pairs, have all been tested by me, or by my assistants, and many hundred useful pairs have been found...", backup

[GWP-1] G. W. Pickard, "How I Invented the Crystal Detector". Electrical Experimenter, vol. VII, no. 4, p. 325, Aug. 1919 Citat: "...In 1898, when my work in Radio-communication began, there was but one detector—the coherer...In the period 1902 to 1906, I tested many different minerals and combinations, including magnetite, pyrite, galena, molybdenite, silicon and zincite. Much development was also required on holders for these minerals...31,250 Crystal Detectors Invented. A list of the several thousand materials I have tested would make dry reading. Suffice it to say that I have found some tzvo hundred and fifty minerals and furnace products which make operative detectors, cither against metallic contacts, or in combination with other minerals. The possible combinations of these two hundred and fifty substances amounting to some 31,250, pairs, have all been tested by me, or by my assistants, and many hundred useful pairs have been found...", backup

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Diodemodtager

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