The diagram shows a tone control with the LM381 IC. The circuit is from a Radio Electronics from February 1990. The power supply is simple.
May 2017 - Texas Instruments' new OPAx388 operational amplifiers can now be purchased from Mouser...
Based on components from Linear Technology, we find this circuit in a 2005 manual. The circuit...
This circuit was found in an American documentation from 1969. Indications of the used transistors are...