We found this circuit in a 1980s American documentation. The operational amplifiers of the integrated circuit used can be common types in an experimental setup.
This is one of the channels of an amplifier suggested by Westinghouse in 1970s documentation. The circuit...
The basis of this circuit is a double T in the feedback, which has the components calculated to...
This circuit was obtained from American documentation from the 1990s. The transformer can be a car...