How to make Lie Detector

In this article, you will learn how to make a simple lie detector easily with less number of components.

Lie Detector

Components Required

  • Resistors
    • 1 – 470 Ohm
    • 1 – 47k Ohm
    • 1 – 10k Ohm
    • 2 – 1M Ohm
    • 1 – 50k Ohm Potentiometer
  • Capacitors
    • 1 – 100nf
  • Transistors
    • 2 – BC547 transistors
  • 1- Red LED
  • 1- Green LED

Lie Detector Circuit Diagram

Lie Detector Circuit Diagram

Lie Detector Working

This circuit is a simple demo model for lie detector . It actually doesn’t determine a lie or truth. It is to just have fun with your friends.

While coming to the working of the lie detector circuit, it works by the phenomenon of change in skin resistance. If a person is saying lie, we assume that he/she will get sweat. Due to the sweat, the resistance of the skin becomes low. This circuit determines the low resistance as lie and high resistance as truth.

You can adjust the sensitivity of the circuit, by adjusting the potentiometer.

You can further find the working, in the video above.

Download Lie Detector circuit and gerber files

If you have any queries, feel free to comment below.

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