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Thread: A question for Engineers! Esp those who specialise in RFID

  1. #1
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    Default A question for Engineers! Esp those who specialise in RFID

    Need to know if there's something like an RFID chip that comes with a light as a visible location marker, doesn't require batteries or any power source to activate it. All u need is a corresponding device (which can be battery powered) like a car remote to signal to the chip to light up for 10secs.

    Is there such a device around? If so, where can I buy it?

    The idea is to paste the chip (which has a size limit of a 20cent coin) permanently onto a wooden marker which would be placed hidden amongst hundreds and thousands of smiliar markers and to identify the marker easily after 5yrs, 10yrs, 20yrs or 100yrs.

    That's the aim.

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    Default Re: A question for Engineers! Esp those who specialise in RFID


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    Default Re: A question for Engineers! Esp those who specialise in RFID

    The RF coil on the tag will not be able to power an LED if thats what you're thinking of. Instead rely on good old logistic goods placement and inventory measures to locate your item.

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    Default Re: A question for Engineers! Esp those who specialise in RFID

    Sadly...

    BTW, are there any passive LEDs that are not battery powered, yet can light up or flash upon the detection of RF waves like mobile phones within a 10 to 15m range?

    I'm looking at such marker LEDs which has an approximate lifespan of between 10 to 20yrs without changing batteries.
    Last edited by jsbn; 20th February 2007 at 10:48 PM.

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    Default Re: A question for Engineers! Esp those who specialise in RFID

    Quote Originally Posted by jsbn View Post
    Sadly...

    BTW, are there any passive LEDs that are not battery powered, yet can light up or flash upon the detection of RF waves like mobile phones within a 10 to 15m range?

    I'm looking at such marker LEDs which has an approximate lifespan of between 10 to 20yrs without changing batteries.
    Light is energy. I don't think you can create energy out of nothing or you would be rich by now. However, I think it would be possible to have something like an LCD which can change colour when there is RF wave impinging upon it and you can detect the change by shining a light over them.
    Last edited by lsisaxon; 21st February 2007 at 02:43 AM.

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    Default Re: A question for Engineers! Esp those who specialise in RFID

    Quote Originally Posted by jsbn View Post
    Sadly...

    BTW, are there any passive LEDs that are not battery powered, yet can light up or flash upon the detection of RF waves like mobile phones within a 10 to 15m range?

    I'm looking at such marker LEDs which has an approximate lifespan of between 10 to 20yrs without changing batteries.
    i believe there is. remember those old cellphone radiation blocking coil/stickers? some of them has an LED integrated into them that flicker when calls are being made.

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    Default Re: A question for Engineers! Esp those who specialise in RFID

    you either need your RF source to be within 1cm of the LED and orientated in the correct direction or your RF source is damned strong.

    For present technology, I would say it's not too feasible.
    “How fortunate for leaders that men do not think.” - Adolf Hitler

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    Default Re: A question for Engineers! Esp those who specialise in RFID

    Quote Originally Posted by yanyewkay View Post
    you either need your RF source to be within 1cm of the LED and orientated in the correct direction or your RF source is damned strong.

    For present technology, I would say it's not too feasible.
    Yeah.. like ~1W of RF power pumped directly into the LED and then the phone keeps dropping connection.
    Last edited by lsisaxon; 22nd February 2007 at 02:28 AM.

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    Default Re: A question for Engineers! Esp those who specialise in RFID

    Quote Originally Posted by yanyewkay View Post
    you either need your RF source to be within 1cm of the LED and orientated in the correct direction or your RF source is damned strong.

    For present technology, I would say it's not too feasible.
    Argh.... Too close.

    The expected distance I'm looking at is like 10m.

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