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IR circuit!!!

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You should try reading the document. It says it's modulated at 38khz in the second paragraph. Basically standard IR remote frequency. It should be relativly resistance to ambient light, but direct sunlight is not to be triffled with, it can so overpower even a modulated signal that the receiver can't detect it. IR outdoor on a sunny day is a bad idea at best.
 
Sceadwian said:
It should be relativly resistance to ambient light, but direct sunlight is not to be triffled with, it can so overpower even a modulated signal that the receiver can't detect it. IR outdoor on a sunny day is a bad idea at best.

I agree that operating an IR detector in sunlight presents certain challenges, and some may not consider it a "good" idea. That is not to say it will not work. It may be the only option, and can work quite well.

As an example, I have attached two photos of a latch/cam that is open and closed. The problem was to detect the state of the latch. The distance from the metal frame (yellow) to the object was about 1 to 2 cm. Various options were tried. A wiper wire worked, except in the outdoors, rust on the surfaces made it tempermental. Inductance was tried, but the distance was just a little too great, and the steel frame created its own set of problems. Common ultrasonic was not sensitive at that distance. High-frequency (e.g, 500 KHz) ultrasonic had too narrow a detection window. Capacitance was too sensitive to other happenings in the environment.

Thus, I went to IR. The IRED emitter is seen on the surface of the plastic cover as the round object with the lens. The detector is under the filter, which is just smoked plastic. The following link gives the reference to where I got the idea, program, and schematic.

https://www.electro-tech-online.com...etection-using-tsop1738-with-pic16f628.30480/

In short, the device has worked outdoors for over a year in various lighting conditions from cloudy and rainy to bright sunshine. It has never failed to detect the state of the latch, nor am I aware of any false signals it has given.

John
Edit: The short piece of blue tape makes the approximate location of the IR detector.
 

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jpanhalt said:
I agree that operating an IR detector in sunlight presents certain challenges, and some may not consider it a "good" idea. That is not to say it will not work. It may be the only option, and can work quite well.

I would agree that it should work with no problems, the IR receiver IC's are VERY good - and over such a short range will give no problems.

Where sunlight may have an effect is if you're trying to use it at remote control ranges (10m plus) with bright sunlight directly on the receiver - but you could simply put the receiver in a tube.
 
nice , now i tried to test the IR reciever and the transmitter so i simply wired them in a breadboard.

but i have a aproblem so i'll tell the connection i did.

IR LED + connected with 1 kohm and the vcc 12 volt
IR LED -connected to GND

IR reciever Pin1 = output connected to Voltemeter +
IR reciever Pin2 = GND
IR reciever Pin3 = vcc connected to 1kohm and then 12 volt

Result :

the voltmeter indicate 6 volt all the time even when i remove the IR LED ., why that happens.?
 
The receiver is fried.

The max allowed operating voltage is only 5.5V. You fed it 12V.
The max allowed output current is only 3mA. You loaded it to 12mA.
It operates at 38kHz, not with a steady IR beam.

Next time look at the ratings on its datasheet.
 
The 1k resistor made a very sloppy power supply voltage that is too high. It should be a regulated 5V supply or 5V fed through a 100 ohm resistor then decoupled with a capacitor as shown in its datasheet.
 
test the receiver with a tv remote controller or other,the output voltage should be changed when you press key of controller.if output voltage does not change,the receiver is burned-out.
 
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