The principle of digital stethoscope

Traditional stethoscope simply transmits the biological sound and the sound does not undergo any processing. Therefore, the biological sounds which you heard are mixed with many noises. It is difficult to catch some important but imperceptible biological sounds. However, the digital stethoscope is different. The digital stethoscope overcomes the shortcomings of the traditional stethoscope. This can be derived from the analysis of the composition of the digital stethoscope. The digital stethoscope mainly includes four parts of the core device—the pickup sensor, the amplification and filtering circuit, the processing chip and the Bluetooth module (some products do not have Bluetooth module).

The main function of the pickup sensor is to collect the auscultation sound. When the diaphragm is in contact with the human body and vibration is generated. The sound wave signal emitted from the human body is converted into a radio wave signal.Most digital stethoscopes on the market use piezoelectric pickup sensors, while Hedelong uses capacitive pickup sensors. Capacitive pickup sensors can better to catch biological sound. The amplification and filtering equipment amplifies the biological sound to a corresponding multiple, allowing you to hear the biological sound clearly. The processing chip is used to reduce the noise interference and ensure to achieve the desired sound data. Excellent noise reduction technology can eliminate almost all the environmental noise. Moreover, Hedelong sound sensing technology can achieve the  distortion rate of less than 1.5%.

The Bluetooth module is used to connect the smart terminal. The collected auscultation sound data is transmitted to the computer, mobile phone and tablet for further analysis. Besides, it can be uploaded to establish the patient’s electronic medical record, and viewed online with partners. In addition, the digital stethoscope with Bluetooth module can support telemedicine.