RF transmitted power Legality / Codes.

I'd like to power some LED devices "remotely" using transmitted power. I've seen there are Instructables related to this
I'd like to create a power source that could energize a small LED circuit at a maximum distance of ~3 meters.  Even better, build an adaptive control, ensuring additional circuits are adequately powered, but design-limited to a safety max.

My concern is to ensure the power source conforms to applicable United States regulations / codes.  I have a background in physics, but no experience in electrical engineering or contracting.  So I really don't know where to begin translating theory into device.  Can anyone suggest advice / guidance / starting references :
  1. What is the legality in the United states?
  2. Are there any codes that apply / regulate transmitted power?
  3. Pro tips?
Muchas gracias for guidance and suggestions!

CarLoz

Transmitted power.jpg
8 answers
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Nov 18, 2009. 2:56 PMNobodyInParticular says:
FCC regulations make exceptions for experimental devices, provided they aren't disrupting the function of approved devices.

If you are making a device for everyday use, resonant induction should avoid most legal problems. You are basically constructing an AM transmitter tuned to a specific frequency and matching this with a crystal radio tuned to the same frequency. (Electrical engineers- please correct my layperson's understanding.)

I would start researching the links provided on Wikipedia and examine patents for current devices.

http://en.wikipedia.org/wiki/Wireless_energy_transfer
http://en.wikipedia.org/wiki/LRC_circuit
http://en.wikipedia.org/wiki/WiTricity


Other thoughts:

* You might use two regular LEDs wired in parallel in opposite directions or use a two-color LED. Otherwise you will be losing half of the recieved power.

* Have you considered using a laser and solar cell instead?
Nov 17, 2009. 2:55 PMsteveastrouk says:
Given the range, magnetic induction would work just fine, run a coil around the area to be energised, power that with an audio amp, at a nice high frequency, and then make a search coil.
Nov 17, 2009. 5:30 PMSandisk1duo says:
transmitting power, to power thing is pretty legal...  unless you are jamming a signal....

it you keep the output power low, you can transmit whatever you like
Nov 18, 2009. 4:31 PMseandogue says:
If you're working at low frequencies, are working at short distances (which requires very low power transmitters, btw) and aren't commercializing the end result, I really  wouldn't worry too much about FCC regs, especially if you're using single chip transceiver solutions. Most of the commercial traffic is way above the "citizen's" band, and the FCC's men-in-black won't be showing up at your door any time soon...Now if you start interferring with your local Police bands using a proprietary design that you've created yourself, that state of being might change pretty quickly...

There are many legal codes and you can get them by visiting the FCC.

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