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:
Feb. 26, 1991
Filed:
Aug. 11, 1989
Motokazu Kashida, Tokyo, JP;
Toshiyuki Masui, Kanagawa, JP;
Tsutomu Fukatsu, Kanagawa, JP;
Masahiro Takei, Kanagawa, JP;
Kouji Takahashi, Kanagawa, JP;
Tomohiko Sasatani, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An audio signal recording apparatus comprises a detector for detecting a silent part of an incoming audio signal within the audio signal corresponding to less than a threshold value and generating a detection signal, a circuit for generating a reference signal of a predetermined frequency, a modulator for modulating the incoming audio signal to produce a modulated audio signal, a circuit for superimposing the reference signal on the modulated audio signal in response to the detection signal to produce a recording signal, and a recording circuit for recording the recording signal on a record bearing medium.