This circuit was suggested by Linear Technology in documentation from the 90s. The circuit applies to modern operators with modern transistors.
This first order Butterworth filter is tuned to frequencies around 1 kHz. The frequency is given...
This very low current circuit was found in the April 1995 Electronics Now magazine. The frequency...
This circuit was found in an American 1980s documentation. It makes use of an unusual MOSFET today...