This circuit was found in a 1968 Motorola documentation. The circuit can be implemented with virtually any photo transistor and general-purpose transistor.
Found in a Hands On Electronics from the 90s, this circuit can be easily assembled today, as the...
This circuit must be powered by a symmetrical source and depending on the integrated circuit the...
This circuit was found in a 1964 Electronic Design. The transistors are of the time, but can be...