Obtained from an Electronic Engineering of the 90s, these circuits can be applied to almost any operational amplifier. Signal shapes are given next to the diagram.
This timer was found in a 1994 Electronics Now. The relay must be a sensitive type. If it has a...
We can make an oscillating relay producing a rectangular signal taking advantage of the inductance of...
This circuit appears at various points in this section and on this site, with minor variations. It uses the...