The circuit shown was found in the 1994 National Semiconductor's Linear Application Handbook. The op amp admits equivalents and the power supply must be symmetrical.
This circuit is valid for 106 series SCRs and can be modified to operate on the 110V power grid....
Found in an October 1992 Radio Electronics magazine article, this circuit generates a low-power tone in...
This circuit was obtained in a Popular Electronics of the 90s. The circuit is compatible with...