This oscillator produces an audible signal on a piezoelectric transducer. The frequency is determined by R2, R1 and the capacitance of the transducer. We found the circuit in the 1994 National Semiconductor Linear Applications Handbook.

This oscillator produces an audible signal on a piezoelectric transducer. The frequency is determined by R2, R1 and the capacitance of the transducer. We found the circuit in the 1994 National Semiconductor Linear Applications Handbook.