This shield circuit can be used in several applications that involve a feedback signal. The circuit is from American documentation from the 80s and the transistors are according to the loads driven.
This interesting circuit measures the distortion of the sinusoidal voltage of the power grid. We...
The operational amplifier used in this old application is not common today, but more modern...
Used in 1950s CW receivers, this type of circuit used germanium transistors. The circuit has...