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Dark Sensor [Very Simple]

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I already made the circuit. Its already working. Can you please explain to me the necessity of those corrections you made with my previous circuit?

Thats good.:)

You may see that the LED comes on and goes off 'slowly', thats because there is no 'positive' feedback from the output to the '+' [non inverting input of the 741].

The way you had it connected was that nearly all the output signal was being fed back to the inputs.

You say you have only got 10K maximum value resistors.!!

What we need now is a 1M0 resistor from pin7 to pin 3, this will make the circuit switch quickly On/Off.
 

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Yeah I know it's property regarding light/dark.

First question about the circuit, the op amp we have here is an inverting one, right?

hi,
I asked the light/dark question so that you would tell me the resistance of the LDR when its light and dark.! not its properties.:)

The 741 has two inputs marked + [non invering] and - [inverting] so its either inverting or not, it depends how you connect the input.
 
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