Can someone give me a material list for Ir transmitter and receiver?

Discussion in 'The Projects Forum' started by rrpking, May 18, 2013.

  1. rrpking

    Thread Starter New Member

    Jan 20, 2013
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  2. wayneh

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    Sep 9, 2010
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    Almost all the parts except the transistor are labelled. The transistor needs to be an NPN type or you could choose an n-channel MOSFET as well. Just about any will work, but must be rated for the current you drive through the IR LED. Your choice of IR LED will depend on the power you need. Distance, battery life, wavelength, cost and such all factor in. It's your choice.
     
  3. wayneh

    Expert

    Sep 9, 2010
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    Actually I don't think a MOSFET likes to see a negative voltage on its gate, so forget what I said about using a MOSFET. Unless someone jumps in and corrects me on the gate voltage issue.

    I guess I might as well also ask: Why not use a standard 555 timer circuit for this? You might be able to drive your LED directly from the 555 output and not need an external transistor.
     
  4. rrpking

    Thread Starter New Member

    Jan 20, 2013
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    I'd like to use a 555 but I am not advanced with circuits yet. I just was really interested in this. Okay so I can buy all the resistors, the 555, the switch, the capacitor. But I still don't know if there is a specific LED indicator, and what section would I find it in?
    If this helps, there is also a picture of the transmitter.

    http://home.engineering.iastate.edu/~wolfkodi/ee230/images/ir-3.jpg
     
  5. wayneh

    Expert

    Sep 9, 2010
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    No, just about any normal LED will work fine for the indicator. Pick the color you like. That 1kΩ resistor will limit the current to (9v-Vf)/1000Ω = ~6mA and that's fine for an indicator. Reduce the resistor to 470Ω if you need more brightness.

    You might want to watch for a wide dispersion of the light. Many LEDs use a lens to focus the light into a tight beam, and then the supplier can claim a high brightness. They are bright if you're in the beam, but much less so off-beam. They also make diffusers you can use to spread the light.

    "Generic" LEDs also vary hugely in efficiency - the amount of light for the power supplied. The dimmest ones I've had came from Radio Shack. I think as long as you get a "modern" LED labeled "super bright" or such, you'll be happy.

    BTW - I highly recommend taking the plunge to learn about the 555. It's very useful for a lot of projects and it is the most used IC in history. Nothing wrong with learning about op-amps also, but the 555 is the right tool for this job, in my opinion. You'll be able to use a single supply, for instance, of 9V or 18V or whatever is convenient. You can find a lot of help here for using the 555 in LED projects.
     
    Last edited: May 18, 2013
  6. rrpking

    Thread Starter New Member

    Jan 20, 2013
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    Okay great I'll let you know if any other questions arise since you seem to be super helpful.
     
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