This tone control was obtained in a Signetics documentation of the 90s. The integrated circuit can be practically any operational amplifier. The power supply is symmetrical.
This circuit consists of two stages that each shift 180 degrees the signal. The circuit was...
This simple battery tester uses two transistors to drive LEDs of different colors, indicating the...
Found in 90s documentation from Analog Devices, this circuit employs operational amplifiers of the time....