This circuit with 24 dB per octave attenuation was found in the November 1973 Radio Electronics magazine. The components are for 1 kHz but can be recalculated for other frequencies.
Using 4 operational amplifiers this circuit generates 4 different tones. The circuit is from an...
In the figure we have an application of an oscillator 4013 as voltage multiplier. It consists of a...
This Colpitts crystal oscillator was found in an American publication for amateurs in the 1980s....