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.
The circuit that gave rise to this configuration is from 1978. In the original publication are...
We found this circuit in Popular Electronics from 1992. Time is given by C1. The circuit provides an...
This circuit was obtained in a 1980 publication but can still be assembled today with the 106...