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Henry Harrison Chase Dunwoody


  Highland County, Ohio 1842-1933
1906 Detector to carborundum (Silicon carbide)


HC Dunwoody American patents the radio detector crystal with carborundum, an essential element for the new industry of wireless telegraph. One of the first components for the detection of radio waves, the crystal carborundum allows the current entry in one sense , so that only the top half of the EU modulated get through.  The work of Dunwoody on a crystal enabled the first radio amateurs to build the first receivers and hear radio previews. The carborundum is composed of silicon carbide and other materials.