This circuit was found in a Popular Electronics from the 90s. The circuit uses a general purpose JFET. The coils depend on the signal range that must be amplified.
This circuit appears in other articles and suggestions for circuits in this section from other...
This tone control was obtained in a Signetics documentation of the 90s. The integrated circuit can be...
We found this circuit in an American publication from the 1990s. Any FET can be used. The circuit...