tedshred
Newly Enlightened
In our lifetime? I'll venture yes. They are figuring it out for other devices, so it's just a matter of time.
http://tech.yahoo.com/blogs/null/143945
http://tech.yahoo.com/blogs/null/143945
What if radio waves could power a LED?
- Thread starter tedshred
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LukeA
Flashlight Enthusiast
Another Nikola Tesla concept. It's interesting, but the same as it was in Tesla's time, hideously inefficient.
Illum
Flashaholic
radiowaves so far has been found to be able to
hmm...
its not a direct process.
Generally, it is accepted that everything vibrates under a specific frequency, it is said that if two objects oscillate at the same frequency, energy can be passed from point A to point B very easily...such was the case for inductive charging, but that was wire coils in close proximity...like a toothbrush
- cook turkey [WWI radar experiment]
- breakdown salt water into fuel [http://www.wpbf.com/news/13383827/detail.html]
- and now it can power LEDs...:candle:
hmm...
its not a direct process.
Generally, it is accepted that everything vibrates under a specific frequency, it is said that if two objects oscillate at the same frequency, energy can be passed from point A to point B very easily...such was the case for inductive charging, but that was wire coils in close proximity...like a toothbrush
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Coop
Flashlight Enthusiast
What if radio waves could power a LED?
Well, we'd need to get shielded toilets, or get used to having the sensation of peeing on an electric fence everytime we have to go...
Well, we'd need to get shielded toilets, or get used to having the sensation of peeing on an electric fence everytime we have to go...
idleprocess
Flashaholic
Interesting concept, but it's hard to imagine pulling a consistent 5mW from the ether at random, nevermind 20mW. Given the lack of details, I expect that those are peak rates in the lab (parked right next to a 240V 3-phase mains line near a leaky microwave), not average. If there was that much energy to be had from stray RF, I expect that cell phone cancer worries wouldn't be so baseless...
Illum
Flashaholic
shielded toilets...
If I didn't know better, I'd say there's a reason why outhouses were removed for you telecom operators, its way too dangerous to be outside at peak usages:nana:
we've already found that applying AC to a hotdog can power an LED...shall we progress down this route?
alpg88
Flashlight Enthusiast
- Joined
- Apr 19, 2005
- Messages
- 5,336
nokia just announced, they build a cell phone that charges off radio waves.
when i was a kid i build small radio reciver that didn,t need battery, it was weak, required very low draw headphone to listen, volume was very low, but it worked,
when i was a kid i build small radio reciver that didn,t need battery, it was weak, required very low draw headphone to listen, volume was very low, but it worked,
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Illum
Flashaholic
ahh, long live those memories...the ones you can buy look like little rockets and you can adjust by pulling a small chunk of ferrite through a coil..
Many people doesn't know this, but LEDs can also be used to create voltage differentials in the presence of light, but its useless unless paired with some sort of amplifier and can be used to detect certain spectrum of light depending on the selection of the LED to create a linear relationship between voltage and light received. I think if it can be used in conjunction with this radiowave availability we might be able to see the elimination of roadlight power grids altogether
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A crystal set is what that small radio is called as a kid growing up in the 50's I built quite a few with the help of my dad and the volume wasn't necessarily low depending on your aerial, earth connections and headphones.
We also used to get a florescent tube going at almost full brightness but touching against the aerial on a mobile AM Ham radio transmitter, once the tube was started you could move away from the antenna with the tube glowing in your hand. I'm sure a LED with a tuned circuit and small antenna will glow in similar circumstances.
Fluorescent Tube Glow in High Potential Field
Lumenshroom
Newly Enlightened
A slightly different frequency already does this- see the microwave.
Illum
Flashaholic
:lolsign:
Coop
Flashlight Enthusiast
A little off topic, but a story that stuck with me:
The story goes that the microwave oven concept was discovered by a radar technician. Who found that a bar of chocolate in his pocket had melted while he was working on live radar equipment. He didn't think much of it until he realized it was freezing at the time.
Actually, there was another reason for this. It was due to a groundbreaking new technology called 'Indoor plumbing'.
The story goes that the microwave oven concept was discovered by a radar technician. Who found that a bar of chocolate in his pocket had melted while he was working on live radar equipment. He didn't think much of it until he realized it was freezing at the time.
shielded toilets...
If I didn't know better, I'd say there's a reason why outhouses were removed for you telecom operators, its way too dangerous to be outside at peak usages:nana:
Actually, there was another reason for this. It was due to a groundbreaking new technology called 'Indoor plumbing'.
Lumenshroom
Newly Enlightened
Just a folk-tale. The frequency isn't sufficient to heat things, especially at that power and dilution. A microwave focuses 1600+watts of electricity worth of microwaves on food.
Coop
Flashlight Enthusiast
LukeA
Flashlight Enthusiast
Lumenshroom
Newly Enlightened
Microwave waves aren't the same thing as radio waves. He said radio.
Mike Painter
Flashlight Enthusiast
- Joined
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The inverse cube law applies.
1000 watts at 1 foot will be 10 watts at 2 feet.
About 2 watts at 3 feet and go down from there.
This ignores the input wattage and anything that would impede the signal along the way.
Within about 10 feet or so you would need an antenna, a battery, and sensitive equipment to amplify the signal.
LukeA
Flashlight Enthusiast
Don't attack the straw man with me. Coop related a story, which he admitted was off-topic, of Percy Spencer discovering the fact that microwave radiation could cook food. You said it was a folk tale. That's false; the story is true. I never said non-microwave radio waves could cook food.
Lumenshroom
Newly Enlightened
Yeah, but he said it was radio waves that did it.
Tell me what they are if they aren't radio waves.
