Temistocle Calzecchi-Onesti

Temistocle Calzecchi - Onesti (* December 15 1853 in Lapedona, † October 22, 1922 in Monterubbiano, brands ) was an Italian physicist who undertook electrical experiments, which formed one of the foundations of wireless telegraphy.

Life

Calzecchi - Onesti studied physics at the University of Pisa and then was initially employed as a high school teacher. 1884 to 1886, he noted that metal chips that do not lead in a glass tube between two brass plates the electricity normally reduce, under the influence of an electrical discharge or electromagnetic wave their electrical resistance of several megohms to a few hundred ohms. This effect is exploited in the so-called coherer or coherer.

His reports on these precursor of the coherer in the Italian magazine " Il Nuovo Cimento " but found in the professional world outside Italy little attention, so that the invention is often attributed to the French physicist Édouard Branly, although until 1890 came out. Calzecchi - Onesti beat the device as a thunderstorm detector before, and so it used also the first twenty years of Guglielmo Marconi in 1894, before he used it a year later as a receiver in his first radio.