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Changing the sensor Answered

Hello guys,

I want to make this circuit I just don't want any light to be visible. So, I was wondering if I could just change this LDR sensor to a IR sensor and still get the desired results. 

Thanks,

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user
Orngrimm (author)2012-12-06

Sure you can do that.
Just take an LDR with its sensitivity in the Infrared range. According to Wikipedia @ http://en.wikipedia.org/wiki/Photoresistor:

"indium antimonide (InSb) LDRs (light dependent resistor) are used for the mid infrared spectral region"

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HavocRC (author)Orngrimm2012-12-06

Oh Ok that sounds better. Yeah I had know idea what type of IR sensor mPilch was talking about. But then again, I don't know that much about electronics. I'm getting along though in my Electronics For Dummies book!

So, an LDR that works in the IR range.

Thanks Origami

~electronicnoob

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user
Orngrimm (author)HavocRC2012-12-06

Origami? :)
Not my name, but i appreciate the thanks! :D

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user
HavocRC (author)Orngrimm2012-12-06

Oh well I like to name people :P

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mpilchfamily (author)2012-12-05

So you want to use an IR beam of light to activate and deactivate the LED?

An IR receiver works a lot differently then an LDR. An LDR is just a resistor that varies it's resistance based on the amount of light hitting it. An IR sensor has 3 pins, ground, voltage, and output. When IR light hits the sensor it will change the voltage and current on the output lead. A simple 555 timer circuit won't cut it when dealing with IR. Look into using a micro controller to help detect an IR signal.

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HavocRC (author)mpilchfamily2012-12-05

Oh ok. But what about the IR receiver on the top of my little walkbot? It's only got two pins coming out of it.

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