As a kid I made a crude version of this. It was in a magazine as a
"Science Museum" headphone device. Just wind a turn of wire around
your bedroom, hook it to your stereo speaker output (with a load
resistor in series,) then receive the magnetic signal with a Radio
Shack telephone suction-cup coil driving a small amp and headphones.
Baseband audio, no resonators. But if you lay down on the bed, this
turns the receiving coil 90deg, and the music goes away.
(((((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))))))
William J. Beaty
http://staff.washington.edu/wbeaty/
beaty chem.washington.edu Research Engineer
billb eskimo.com UW Chem Dept, Bagley Hall RM74
206-543-6195 Box 351700, Seattle, WA 98195-1700