Electronic Auscultation System: a Method for Measuring the Amplitude-Frequency Characteristics of Stethoscopes

   The purpose of research is increasing the diversity of designs of electronic auscultation systems with measured characteristics and testing.   A series of articles includes the development of a model of an electronic auscultation system, the development of an electronic stethoscope design, the manufacture of an experimental sample, the development of a method for measuring the amplitude-frequency characteristics of electronic and classical stethoscopes, testing the proposed models and methods, and analyzing auscultatory data. The article proposes a method for measuring the frequency response of classical and electronic stethoscopes. The proposed method was tested. The frequency response of classical and electronic stethoscopes was measured. The design of the head of the electronic stethoscope has been improved, the frequency response of the original and improved designs has been compared.   Methods. The studies were based on methods for measuring the frequency characteristics of electroacoustic transducers proposed in interstate standards. On the basis of methods in interstate standards, a simplified method for measuring the amplitude-frequency characteristics of electronic stethoscopes has been developed. The following equipment was used in the study: Type 4227 "Artificial Mouth" emitter from Bruel & Kjaer; measuring condenser microphone "Artificial ear" Type 4146 with a 2CC reference chamber from Bruel & Kjaer; Type 2118 analyzer from Bruel & Kjaer.   Results. The amplitude-frequency characteristics of classical and electronic stethoscopes are obtained. The design of the electronic stethoscope head has  been improved, the amplitude-frequency characteristics of the original and improved designs have been compared.   Conclusion. A method for measuring the parameters of the frequency characteristics of the sound pressure level of classical and electronic stethoscopes is proposed. The method is as close as possible to the standardized methods for monitoring acoustic parameters, while being sufficiently simple and cheap compared to the pressure measurement method, demonstrating the qualitative similarity of the measurement results.