Like many of these there is a grain of truth to be found.
When I was in high school I had "perpetual free" classical
music in my room every day from about 6:00 am to midnight.
The device was called a crystal radio. I easily powered a
speaker with the programming from nearby WHLI AM. I don't
know how much power it took to drive the speaker but I
suspect it was not a lot. If I recall correctly, I think it
was about a four inch speaker. (Half a century has dulled my
memory a bit.)

Allen

> -----Original Message-----
> From: piclist-bounces@mit.edu [mailto:piclist-
> bounces@mit.edu] On Behalf Of Charles Craft
> Sent: Wednesday, September 30, 2015 12:07 PM
> To: PIClist
> Subject: [EE] Perpetual Power (tm)
>=20
>
http://arstechnica.co.uk/gadgets/2015/09/freevolt-perpetual-
> free-rf-energy-harvesting-to-power-the-internet-of-things/
>=20
> I think I've learned here on the piclist to run when the
words
> "perpetual" and "energy/power" are used in the same
> sentence. :-)
>=20
> "Freevolt harvests free volts (!) from a wide variety of
RF
> radiation sources, which can then be used to power the
various
> sensors and microcontrollers that make up the (are we
there
> yet?) Internet of Things."
>=20
>=20
>=20
> --
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> archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist

--=20
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