We found this circuit in a Poptronics from the 90's. Equivalent operational amplifiers can be used. The circuit must be supplied by a symmetrical source.
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...