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Lowest power required to light up an element, be it LED of light bulb or Neon? Answered

What  component (led, bulb, neon...) needs the absolute minimum of energy to light up even dimly ?
What I would like to do is to make something like RFID (no batt) that would be able so sense RF field from some distance, 2-3m.

Thank you.

Tags:rfid

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user
lemonie (author)2011-10-14


What's this RF field then?
(it makes a difference)

L

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user
nccwarp9 (author)lemonie2012-05-30

As mentioned earlier, lets say you are about a mile from a large radio tower.
I know that radio receivers can be made to work without batteries.

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user
lemonie (author)nccwarp92012-05-30

Yes, just build a tuned-circuit with a big aerial. Look up radio receiver circuits.

L

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user
steveastrouk (author)2011-10-14

Fluorescent tubes will light quite brightly from leakage currents through the glass, in a dark room.

However, "RF fields" can vary from picowatts to many watts. What (!) have you got available ?

Steve

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nccwarp9 (author)steveastrouk2011-10-21

I was thinking more in the line of using RF from big radio towers or power lines. But at the end the most prevalent RF source today are cellphones. There are instructables on how cellphone can light up an LED but its all close.
As I mentioned it, it need not to be bright.

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user
nccwarp9 (author)2011-10-18

I was thinking more in the line of using RF from big radio towers or power lines. But at the end the most prevalent RF source today are cellphones. There are instructables on how cellphone can light up an LED but its all close.
As I mentioned it, it need not to be bright.

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user
iceng (author)2011-10-14

See the Video attached where a Simple Finger Move  (VeryLow Power)
cause Oxygen to ionize with a spark of Light, by way pressing of two
Cleavite ¼" diameter 1" long  piezoelectric  crystals.  .  .   A

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