This circuit was found in the Electronics Experimenter Handbook from 1991. The sensor is a diode and the circuit has a relay according to the voltage used in the supply.
This project was found in a 1982 publication, using only two transistors. Signal injectors are...
The circuit triggers a warning system after the programmed time interval. The circuit uses a CMOS...
We found this circuit in the 1993 Motorola Linear Interface ICs. The operational is unusual today, but...