We found this circuit in the July 1992 issue of Radio Electronics magazine. An optical system produces the light beam that, when interrupted, triggers the alarm. The sensitivity is adjusted by R4.
This simple lie detector was found in Popular Electronics. Transistors are commonly used. The...
Found in the 2005 Linear Technology Application Manual, this circuit controls the torque of a...
This circuit was found in the Italian magazine Radio Elettronica from September 1977. It consists of a...