This simple audio generator with the 741 was found in a 90sTexas Instruments. The circuit generates sinusoidal signals from 15 Hz to 150 kHz in 4 bands, as shown in the diagram.
This circuit uses a GE optical coupler. Equivalents can be tried. The circuit is from the GE...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...
This circuit is suggested by the Texas Instruments Linear Circuits Applications, based on the FET...