This circuit uses three oscillators to produce a sound similar to a cricket chirping. Two oscillators act as modulator for the third resulting in a tone that is produced by a small piezoelectric transducer. The tone is a chirp" like a cricket makes. The circuit shown here has a very low current drain and can be powered from a 9 V battery. The sound is even more realistic if low-power transducers are used. For a small loudspeaker use a drive stage with a transistor.
Cricket
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