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:
Sep. 15, 1981
Filed:
Mar. 25, 1980
Ryuji Yamamoto, Tonemachi, JP;
Kiyotaka Ohsawa, Kanamachi, JP;
Soundesign Corporation, Jersey City, NJ (US);
Abstract
Recorded features on a recording medium have inter-feature pauses which must be reliably detected in order to control the selective replay of the features. Certain noise signals located within an inter-feature pause complicate the detection of the latter. These noise signals include low-frequency signals which have high voltage levels at playback speed, and middle- and high-frequency signals which have high voltage levels at fast forward or rewind speed. These high voltage levels of the noise signals could be mistaken for audio signals. A signal-processing circuit filters the noise signals from the audio signals. A control circuit changes the impedance of the signal-processing circuit such that the signals are filtered according to a first predetermined filter characteristic when the recording medium advances at playback speed, and according to a different second predetermined filter characteristic when the recording medium advances at fast forward or rewind speed. The filter characteristics attenuate the high voltage levels of the noise signals to low voltage levels, thereby preventing the noise signals from being mistaken for audio signals at the playback or fast forward or rewind speeds.