This configuration can be found in several articles on this site. The one shown in the diagram is from the datasheet of the LM101 series amplifiers, but it can be implemented with other types.
This circuit with signal acceptance filter was found in the June 1993 Electronics Now magazine. Other...
We found this 555 integrated-circuit tester in an old Electronics Hobbyst from 1977. The circuit is...
Found in a1969’s neon lamp documentation, this circuit uses a high voltage transistor. The output...