Phonocardioscope with a liquid crystal display

Claim 1

A phonocardioscope apparatus for monitoring heart functions said apparatus comprising: (a) acoustical transducer means for detecting the sound of heartbeats and producing an analog electrical signal in response thereto; (b) an analog-to-digital converter for converting said analog heartbeat signal to a digital heartbeat signal; (c) coupling means for coupling said transducer means to said analog-to-digital converter said coupling means including an isolation means for electrically isolating said transducer means from the other elements of said apparatus, non-linear amplifier means coupled to said isolation means for non-linearly amplifying the acoustic heartbeat signal, shunt means connected to said analog-to-digital converter in parallel with said non-linear amplifier means, and switch means for selectively applying the output of said isolation means to said non-linear amplifier means or said shunt means; (d) memory means coupled to said analog-to-digital converter for storing the digital heartbeat signal; (e) CPU means coupled to said analog-to-digital converter and to said memory means for controlling the operation thereof; (f) liquid crystal display means coupled to said memory means and said CPU means, wherein at least a predetermined portion of the digital heartbeat signal data stored in said memory means is displayed by said liquid crystal display means and wherein the display of the digital heartbeat signal data is controlled by said CPU means.