The expansion rate of this circuit is determined by R. The circuit can use any operational amplifier and the power supply must be symmetrical. Resistor R must be less than 10k.
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...