The circuit shown in the figure can be designed with more modern operational amplifiers, as it is from 1994 documentation by National Semiconductor. The power supply must be symmetrical.
This defrost alarm starts from an interesting idea. A small magnet on an ice stone is trapped at the...
Found in the Radio Experimenter Handbook in a 1986 edition, this circuit warns when the car's high...
This interesting emitter-coupled circuit was found in the May 1970 issue of Radio Electronics...