Stethoscopes are medical instruments which amplify acoustic characteristics of the internal organs of humans and animals. This information is collected to determine the vigor of hearts, lungs, intestines, veins, and arteries.
When used with a sphygmomanometer it can determine blood pressure.
A tunable diaphragm registers high-pitched noises when it is placed against the eipdermis. An open bell oscillates low pitch sounds and sends acoustic waves through tubing and to the healhcare provider's ears via a headset.
Most stethoscopes are analog devices and draw no power; these are called acoustic stethoscopes. Electronic stethoscopes are less common. Fetal and Doppler stethoscopes are also made.
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