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. 19, 1980
Filed:
Nov. 07, 1977
Patrick S Roberts, Rolling Meadows, IL (US);
Thomas International Corporation, Chicago, IL (US);
Abstract
An electronic organ includes a read-only memory which stores eight bit binary words each having a digital value proportional to the frequency of a different note. When a chord keyswitch is actuated, a corresponding chord selector controlled by a multiplexer circuit causes the randomly addressable memory to sequentially generate binary words corresponding to the frequencies of the notes forming the selected chord. Each binary word is stored in a latch associated with a different universal tone generator capable of generating any tone as controlled by the stored binary word. Each universal tone generator includes a comparator which recognizes a match between the associated latch and a counter which receives clock pulses from a single fixed frequency oscillator. The comparator resets the counter and generates an output pulse which is divided to form an audible tone signal.