This circuit emits a warning sound when night falls. The circuit is from a Hands On Electronics from the 90s. The Sensor is a common LDR and R6 adjusts the trigger point.
This circuit was found in General Electric documentation from 1964. It makes use of a PUT, called the...
This circuit was obtained in a documentation from the 70s. The operational amplifiers used are...
This circuit was found in a documentation for radio amateurs in 1974. It can be used to generate...