Found in Popular Electronics from the 90s, this circuit detects modulated infrared radiation and serves as a test for remote controls. Infrared sensors equivalent to the one indicated can be used.
This interesting logic circuit was found in a manual of neon lamp applications. | Clique na imagem...
This variation of the previous circuit produces a pulsating sound when the sensor is activated. The...
This circuit allows controlling a LASER pointer with an input logic signal. R has 10 ohm for 3 V...