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Message started by rrrafko on 10/30/09 at 11:57:27

Title: example for IR LED
Post by rrrafko on 10/30/09 at 11:57:27
Pls., can you add example, how connect IR LED to analog port(e.g. QED123)? Maybe it's the primitive for someone :) But I'm not sure, how do it (and I think, so I'm not alone here). If is possible, add pls. example, how connect the same LED to a digital port. (I heard that is it possible too). I need it, because is it sanest choice for e.g. linefollower.
Thank You.
BoNo :)

Title: Re: example for IR LED
Post by Vaccumdiode2 on 11/09/09 at 18:35:38
Hello rrafko,
                   Life is a learning process.   This is not a simple as some may lead you to beleive.  First the wiring board works with 0 to 5 DC volts Ranage.  depending on your IR LED you have, it may work or not work.  I believe you want to use it as a sensor to read another IR LED's reflection from the surface your running on.  So you can tell if your sensor is on or off the line.  normally you use a minimum of three.  the more sensors the better.  

                I have done some testing with QRB1134 LED/Phototransister.  Which is simular.   As the light's intencity increaces and decreases the the voltage increases and decreases.  It can be hooked up like a Photoresistor in most cases I believe.  
SEE  http://www.wiring.org.co/learning/examples/photoresistor.html

please post a link to the data sheet for the LED sensor you have and I'll give you a good place to start your testing.
Placement of the sensor and IR light sorce can greatly effect your readings.  

Title: Re: example for IR LED
Post by Vaccumdiode2 on 11/09/09 at 19:04:21

I did some rescreach and found that Your QSD123 Sensor is a Phototransistor.  Here is a link on how to hook it up.  


As the light increases the voltage decreases.  the signal wire goes to the analogRead wiring pin.

I played around eith mine and found that the distance from the surface being read is very impoertant to the range of reading you get.  Let Me know if this helps.

Title: Re: example for IR LED
Post by Vaccumdiode2 on 11/09/09 at 19:34:48
 Another Note:  By change the cap you can adjust the range9more sensitive and less sensitive.  I isaid in my first post there maybe more to it than you would think.  Testing and expirmenting is the fun part anyway.

Title: Re: example for IR LED
Post by barragan on 11/10/09 at 09:37:46
hi there, we were working on the site, still some issues and broken links but lots of new things, check out your diagram here,
thank you Vaccumdiode2, http://wiring.org.co/learning/basics/phototransistor.html

Title: thanks
Post by rrrafko on 01/17/10 at 14:08:46
thank you vaccumdiode :) very much. Don't you know how much did you help me :)
One big THANKS  8-)

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