This circuit turns off after a time given by capacitor C1. This component can have from 1 to 1,000 uF depending on the desired time. The circuit is from an Electronics Now from June 1995.
This optically coupled circuit was found in the February 1968 Radio Electronics magazine. The...
This limit detector or window discriminator uses an old operational amplifier, but it can be...
We found this circuit in a 1974 integrated circuit manual. Operational amplifiers can be of...