Lie detector


Posted on May 30, 2012

The two probes shown are held in the hands and the skin resistance applies bias to the transistor. The 5 k ohm pot is set for zero deflection on the meter. When the ' 'subject'' is embarrassed or lies, sweating on the hands takes place, increasing the bias to the transistor and upsetting the bridge balance.


Lie detector
Click here to download the full size of the above Circuit.

Enjoy!




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