This circuit appears in several versions in publications of the time and can be modified by changing the capacitors. This one is from Radio Electonics magazine from October 1992.
This circuit is from Motorola's Linear Interface ICs of 1993. The circuit can be powered by...
This circuit activates a relay when the supply voltage drops below the value set in the trimpot. The...
Based on National semiconductor power operational amplifiers, uncommon today, this circuit...