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:
Jan. 09, 1979
Filed:
May. 11, 1977
Shizuo Ando, Kawagoe, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Abstract
An audio signal discriminator circuit wherein the discrimination of audio signal is effected by utilizing the difference in peak level changing mode between audio signals and other signals, such as dial tone signals, beep tone signals and the like, comprises a rectifier circuit for rectifying input signals, a voltage hold circuit for holding an output peak voltage of the rectifier circuit, a voltage comparator circuit for comparing the peak voltage held in the voltage hold circuit with the following peak voltages to produce an output signal when the following peak value is relatively high, a time switch for producing an output signal when no reset signal is applied thereto for a predetermined time period, and a gate circuit for transmitting the output signal of said rectified circuit as a reset pulse to the time switch in response to the output signal of the voltage comparator circuit.