I am trying to make a IR sensor but somehow its not working.Below is my circuit diagram
when i bring my hand near the sensor, the led connected to pin1 of lm358N does not glow.
I also checked the voltage at pin2 of LM358N ,it is reading 5v whereas pin3 reads 3.2 v.
when i bring my hand near the IR sensor, the voltage remains same.
I actually tested my circuit using tv remote and found that my IR recevier is working fine so may be transmitter have the problem .so i took my cell phone any saw the transmitter using my cell phone camera but couldn't see anything .I have changed my transmitter but still i cant see radiation in my camera .whereas my tv remote transmitter radiation was visible.what could be the problem?
Best Answer
Measuring 5V at pin 2 indicates that the IR receiver is not conducting any current, which would suggest that: a) it is not connected (try re-wiring that portion of the breadboard), b) it is not being illuminated with enough IR to conduct (maybe the IR transmitter is backwards--try reversing it), or c) it is broken (try another receiver).
Digital cameras, including ones on cell phones are sensitive to IR. Try using a digital camera to see if the IR transmitter is working. You might have to point the IR LED directly at the camera and possibly turn off the lights in the room. You can test it with a TV remote control that you know works.