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ABSTRACT
Electronic stethoscopes require conversion of acoustic sound
waves to electrical signals which
can then be amplified and
processed for optimal listening.
It can be a wireless recording
device, and can provide noise
reduction, signal enhancement,
and both visual and audio output .
INTRODUCTION
Electronic stethoscope is an acoustic medical device for auscultation, or listening to the internal sounds of an animal body usually.
It overcomes the low sound levels by electronically amplifying body sounds.
MOTIVATION
The Electronic Stethoscope is preferred to
normal stethoscope as it hears patient's heart and lungs clearly in high noise environments (up to 100 dB levels), even through layers of clothing.
The ES also makes it possible to hear fetal sounds clearly and to monitor blood pressure through clothing layers.
BLOCK DIAGRAM
SCHEMATIC
LAYOUT
CIRCUIT DESCRIPTION
LM358 : SPECIFICATIONS
LM386 : SPECIFICATIONS
 UA741 : SPECIFICATIONS
APPLICATIONS
It Helps The Doctor Detect The Faintest Abnormality.
Not only useful for doctors, but home mechanics, exterminators, spying and any number of other uses .

ELECTRONIC STETHOSCOPE

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objective:



The aim of technology is to make products in a large scale for cheaper prices and increased quality. Stethoscopes are not only useful for doctors, but for home mechanics, exterminators, spying etc. Standard stethoscope provides no amplification which reduces its use for a certain extent .But an “ELECTRONIC STETHESCOPE” uses op-amps to amplify the signal and includes a low pass filter to remove background noise.


CIRCUIT DESCRIPTION


A Stethoscope operates as a low-noise microphone
pre-amp. Its gain is only about 3.9 because of the high
output impedance of the drain of the FET inside the
electret microphone causes U1a’s effective input
resistor to be about 12.2K. C2 has a fairly high value in
order to pass very low frequency (about 20 to 30Hz)
heartbeat sounds.


THEORY:


An electronic stethoscope is used to listen to your heartbeat and you would normally use a listening tube or stethoscope. This electronic stethoscope circuit uses a piezo sounder from a musical greetings card or melody generator, as a microphone. This transducer has an output signal in the order of 100 mV and its low frequency response is governed by the input impedance of the amplifier.


ADVANTAGES:


Operation of an electronic stethoscope is very
simple and intuitive. The following are the features of
an electronic stethoscope.
.Hear chest sounds, fetal sounds, and check blood
pressure through clothing layers.
.Direct conversion of sound from the chest to
electronic signals minimizes SOUND INTERFERENCE.
.Ideal stethoscope for use in air and ambulance
transport of patients.
.Separate adjustable filter and volume controls.