Using an operational amplifier with FET, this circuit from a 1977 publication can generate sinusoidal signals from 7.5 Hz to 75 kHz in 4 bands. The circuit does not need a symmetric power source.

Using an operational amplifier with FET, this circuit from a 1977 publication can generate sinusoidal signals from 7.5 Hz to 75 kHz in 4 bands. The circuit does not need a symmetric power source.