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:
May. 10, 1977
Filed:
Oct. 14, 1975
Akio Tanaka, Chicago, IL (US);
Zenith Radio Corporation, Glenview, IL (US);
Abstract
An all-channel two mode television tuning system includes a presettable counter for deriving the number of a receivable television channel by counting the local oscillator frequency. The frequency is varied by a ramp voltage circuit under the control of a comparator which adjusts the tuning based upon the difference between the derived channel number and a desired channel number sequentially generated by externally activated channel counters. A 82 .times. 1 bit read/write memory is addressed in the first or program mode by the generated channel number to provide locations for storage of signals for tuning to preselected channels. In the second or operate mode logic circuitry interrupts the advancement of the channel counters whenever a generated channel number corresponds to a preselected channel number.