We found this circuit in a 1965 Electronic Design. Transistors are still common but admit equivalents for some of them. The circuit drains a current of only 4 mA.
This is the receiver circuit for the previous transmitter (CB19628E). The receiver is an infrared...
This circuit was found in old American documentation. Transistor is general purpose and coil rated...
Found in English documentation, this touch sensitive switch must be powered by an isolation...