We found this circuit in an Electronics Now from the 1990s. The circuit crashes when light strikes the sensor. Instead of the alarm a relay can be used to drive higher power devices.
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...