We found this circuit in the July 1988 Radio Electronics magazine. The frequencies are given by capacitor C1 and the voltage input is made at pin 1.
The circuit shown in the figure can be used to connect a loudspeaker to an amplifier only after...
The circuits shown below consist of diode protections against accidental polarity reversal in the supply...
This circuit was obtained from an 80's EDN. The components used are still common. The circuit can be...