The presented circuit was found in the National Semiconductor FET Databook. The setting applies to other operational amplifiers and other FETs. The power supply must be symmetrical.
This circuit uses one of the 6 CMOS inverters of a 4060 as a touch on / off switch. The power...
This aperiodic circuit was found in an old English documentation. The transistor can be any JFET...
This circuit can function as both a light alarm and a shadow alarm. The components are common. The...