3 ms·
http://en.wikipedia.org/wiki/Crystal_radio http://en.wikipedia.org/wiki/Crystal_radio
by dctoedt 12y ago
http://en.wikipedia.org/wiki/Crystal_radio http://en.wikipedia.org/wiki/Crystal_radio
- marcosscriven 12y agoI recall as a kid my mind being blown when I realised you could get enough energy out of "thin air" to drive a little earphone, with nothing more than a length of wire, a finished toilet paper tube, and a crystal/diode.