Patent ID: 6163504
Filing Date: 2000-12-19
Classification: G01H

Abstract:
A signal detector for monitoring sound signals having frequencies over a selected frequency range and for producing output in response thereto, comprising:(a) a first sensor element operative in response to presence of sound signals to produce a first electrical signal;(b) first processing circuitry associated with said first sensor element, said first processing circuitry operative in response to the first electrical signal to amplify the first electrical signal and to produce a first input signal at a selected first input signal amplitude;(c) digitally controlled oscillator circuitry operative to produce a reference signal at a selected reference signal frequency;(d) a mixer operative to receive the first input signal and the reference signal to produce a mixed composite signal;(e) conditioning circuitry operative in response to the mixed composite signal to produce a first amplified output signal; and(f) a first output device for producing a first display in response to said first amplified output signal.