This circuit was found in Raytheon's 1967 documentation. The circuit uses an operating of the era, but the configuration can be applied to modern operational amplifiers.
The components of this circuit are not common today, as it was obtained in the Linear Applications...
Suggested by General Electric documentation from 1968, this circuit activates a relay after 60...
This basic amplifier circuit that can be powered by voltages from 6 to 24 V has the output...