This filter was found in an American publication from the 1980s. The circuit can be implemented with any operational amplifier. The power supply must be symmetrical.
We found this circuit in an old documentation from the 70s. The text is the original one of the...
The circuit shown in figure is suggested by Maxim in an application note. The operational...
We found this amplifier in a 1990 documentation. The transistors are common, having been made...