This photoelectric sensor that triggers a relay was found in an English book from 1989. The transistor is a general-purpose type, and the integrated circuit consists of an operational amplifier.
This circuit is from a 1967 publication. It is possible to power a fluorescent lamp from a 12 V...
This circuit was found in old American documentation. Transistor is general purpose and coil rated...
With a strong positive feedback (via a 10 M resistor) we can get the trigger setting for the...