03982528 is referenced by 13 patents and cites 6 patents.

Circuitry for refinement of fetal heart signals from an ultrasonic (or other mechanical energy) transducer, featuring improved signal processing circuitry connected to the transducer to convert useful information-carrying energy in the transducer output into a refined electrical signal, and improved correlation circuitry for providing an output to a cardiotachometer.

Title
Apparatus for refining signals derived from fetal heartbeats
Application Number
5/552233
Publication Number
3982528
Application Date
February 24, 1975
Publication Date
September 28, 1976
Inventor
Patrick G Phillipps
Newton
MA, US
Assignee
Brattle Instrument Corporation
MA, US
IPC
A61B 5/02
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