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:
Dec. 26, 1978
Filed:
Oct. 21, 1977
Jack D Burton, Orlando, FL (US);
John M Vandling, Pleasantville, NY (US);
Exxon Research & Engineering Co., Florham Park, NJ (US);
Abstract
Frequency modulated pulses representing dark/light variations on a document are applied to a frequency limiting circuit prior to synthesizing a low distortion sinewave voice band signal from the pulses. The frequency limiting circuit detects the frequency of the pulses and divides the frequency when the frequency exceeds a predetermined level. Detection of frequencies in excess of the predetermined level is achieved by a counter which counts clock pulses applied to the counter during each cycle of the frequency modulated pulses to determine the time between pulses and thus the frequency of the pulses. A gate only passes the pulses after a predetermined count has been reached.