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Proximity Switch Schematic !


Wow. A lot of changes. But surprisingly, not the op amp.

All the resistors need to be recalculated based on the diodes/LED Vf and the buzzer based on its rating. Chances are the will be close to 2.6x (24/9) larger.


Well-Known Member
Most Helpful Member
What's the point of the circuit? The only way to turn the buzzer on/off is to turn the pot. The "transmitter" will be on all the time.
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Thanks for your replies, sorry that schematic was just one I pulled from the web to try to explain what I was wanting to do , will explain properly as below !.

"I have a Paper Shredder that ir sensor is not working, changed Caps still no luck, so have given up on that part, the Shredder itself has hardly had much use, the motor works fine ( in reverse ) .

What I am wanting to do is make a small ir proximity paper detector to operate the 24v relay on the main board and dissable the original part of the circuit on the main board, there is plenty of room within the Shredder to put another small board in .
Will attach a schematic of the shredder I made just for info as I will not be using that board for the detecting of a sheet of paper.

So really I am trying to find a schematic for such a project ( I don't like stuff going to the the tip ) is there anyone that can give me the info for me to make a schematic for such a thing ! ".



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