This amplifier is from Motorola's 1990 Linear Databook. The circuit can be used with operating amplifiers with the same characteristics and the power supply must be symmetrical.
Any JFET can be used in this circuit suggested by Electronics Now magazine, April 1993. The...
This circuit allows you to view two low frequency signals on a single channel oscilloscope. It was...
Found in an old Popular Electronics this circuit is still current. The SCR can be of the 106...