Bilateral current source 2 (CB20819E)

We found this circuit in an American publication from the 1980s. Equivalent modern operational amplifiers can be used.

Audio Amplifier and Oscillator (CB14795E)
We found this circuit in a 1964 publication. The circuit is both an amplifier and an oscillator for the...
Alternate Tone Control (CB25834E)
This passive circuit was found in the March 1995 issue of Elexctonics Now magazine. The circuit is for...
Negative Feedback Stage (CB6131E)
This circuit is from a 1967 US publication. The configuration can serve as a basis for designs...