This filter is from a 1977 publication. The circuit employs three 741 or other operational amplifiers. The supply must be symmetrical and the components with (*) are low tolerance.
The more sensitive the instrument used the better the sensitivity of the indicated meter. We...
Based on the 4017 integrated circuit, this circuit of a European 303 Circuits from the 90s,...
The integrated circuit used in this project is unusual and it includes internal transistors that...