• on Audio/Video/Photography
  • Published in issue 12/2003 on page 0
About the article

Card Radio

Card Radio
Among some of our modern contemporaries, ‘musical’ postcards evoke strong reactions of astonishment about hypermodern microcontroller technology. However, such flat melody memories would only have elicited a weary smile from our forefathers. As early as 1928, there are reports that radio cards with the dimensions of a regular postcard and a thickness of only a few millimetres were being made. These cards concealed a basketwork coil with a sliding tap for tuning the frequency of the received signal, a fixed capacitor and a miniscule detector device consisting of a small crystal with a ‘whisker’ contact.
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