This circuit can be implemented with other comparators in the same series. The circuit is from a component manual and the supply voltage between 3 and 12 V depends on the application.
This stethoscope or hearing aid amplifier has excellent gain. It was found in Popular Electronics from...
Found in Fairchild documentation from the 90s, this circuit generates signals with the...
This configuration, widely used in our articles and on this website, uses a 555 to control a relay...