Comment Re:AM Radios (Score 1) 110
I made devices to light up a little LED or move the needle of a galvanometer only using the electricity harvested from radio waves. They are resonators, like most antennas anyway, which implies that they only harvest around a given frequency, say 100 MHz FM broadcast or 900 MHz cell phone communication. The "snake", intended for FM broadcast waves, has a LED that will light up a little bit even a few kilometers away from an average powerful emitter. It can easily feed a low-power LCD calculator.
http://www.4p8.com/eric.brasse...