This circuit was found in a Hands On Electronics from the 80's. The circuit emits an audible alert when dawn and the sensor receives solar illumination.
Found in a 1967 publication by General Electric, this SCR circuit generates voltages of 120 VAC at...
I found this simple circuit an English magazine from 1984. The circuit can be easily assembled by simply...
This circuit also detects IR, providing LED indication. The circuit is used to indicate humidity in...