This circuit is from the 80's integrated circuit manual itself. The component is not as common today as the MOS transistor used. The circuit can be adapted for modern applications.
Today we have more compact solutions. This is from a Radio Electronics magazine from October 1990....
This filter was found in Texas Instruments documentation from the 1980s. The circuit uses a common...
16 commercial test circuit for tubes and transistors appeared in Radio Electronics magazine in...