Design and development of an electronic stethoscope

This paper discusses the design of an electronic stethoscope which is used to listen to the heart and lung sounds. The sounds are captured from the surface of the skin, after which they are filtered and amplified to enable the signal level to exceed the audible threshold. A loudspeaker is used to clearly listen to the processed signals. The signals are sampled, digitised and then analysed using the Fourier Transform to obtain the time and frequency characteristics. The real-time display of the Phonocardiogram (PCG) is provided alongside the calculation of the heart rate. The design of the electronic stethoscope is user friendly and makes the auscultation experience pleasant and worthwhile.