This circuit periodically reverses the rotation of a motor to change the position of eggs in an incubator. The circuit is from Electronics Now magazine, May 1995.
This 4-competitor TTL speed game was obtained in a 1980s documentation, but can still be easily...
This powerful sound emitter used in defense to intimidate people was found in a 90s Popular...
This circuit triggers an alarm when the mains power is cut off. The circuit was found in the July...