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i need help with a very important project [deadline: 21st of January 2014] ?

I need ideas, help, suggestions anything that might help i am trying to make a small 12mm x 9mm necklaces that will light up when a with certain 1in x 1inch watch is within 15 - 40 feet of the necklaces  and the closer they are the brighter it will glow I've looked at wireless power doesn't seem to go far enough with how small I need it so if anyone has a any ideas at all that would be great the most helpful thing would be a schematic I can do the shop and electrics I just need schematics even if there not small or big enough they would still be helpful

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Hunting doge radio collars or electric fence.

But I would rethink that if it is for your girl friend or wife, (Dog Collar).

For your self no problem she might even like it.

I don't think an electric fence based necklace is a good idea...

Especially if she makes you wear it.

Turn it down to light the LEDs of course.

Remember you want something that lights up when your near and that is exactly what an electric fence collar does.

tykora (author)  Josehf Murchison3 years ago

the necklace is suppose to light up the watch isn't suppose to have any kind of indicator that the necklace is near and I just want it to light up when im near by not a tracking system

The electric fence collar instead of a shock LEDs light up.

tykora (author)  Josehf Murchison3 years ago

interesting but im going to work with some experimental technology and wireless power method and there are no 147.7kHz crystals or 0.1477MHz crystals

framistan3 years ago

This method might work. You take a small FM radio receiver. Disconnect the speaker and attach an LED instead of the speaker. You might need to put a small full-wave-rectifier to drive the LED, so it always gets correct polarity. The LED is inside the pendant. Wires would come out of the necklace from behind the neck area of the necklace, and lead down to the radio receiver in her purse or elsewhere. Using an UNUSED frequency on the fm radio dial, all you need to do is transmit a constant tone on the unused FM channel. The transmitter might could be built into a wristwatch. Including the battery and antenna might be a bit of a problem. Most little FM transmitters work about 40 feet away. They sell them for cars on ebay for just a few dollars. My idea I think is somewhat workable, maybe it will help you think of something else or give you an idea.

iceng framistan3 years ago

+1

iceng3 years ago

Look into fox an hound radio clubs