The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 27, 1978
Filed:
Sep. 20, 1976
Ralph M Francis, Jr, Racine, WI (US);
Milwaukee Resistor Corporation, Milwaukee, WI (US);
Abstract
Composite noise and information signals are amplified and filtered to segregate high and low frequency bands that correspond with noise from an intermediate frequency band which corresponds with the information signal. The absolute values of the two noise band signals are summed, weighted, and compared with the information band signal in an operational amplifier whose output tends toward a signal of one polarity with respect to a reference voltage due to noise and tends toward the opposite polarity due to the information band frequency. The signal is integrated and used to control an alarm circuit and environmental noise indicating devices. Means are provided to reduce sensitivity of one of the devices in the presence of high noise and to restore sensitivity if a valid information signal occurs. The other device is used to warn of persistent environmental noise that might be eliminated. The input amplifier of the system is provided with a feedback circuit that brings about compressor action to null the effect of high transient noises.