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:
Mar. 09, 1999
Filed:
Oct. 11, 1995
Applicant:
Inventor:
William T Fong, San Diego, CA (US);
Assignee:
ADcom Information Services, Inc., Carlsbad, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
455-2 ; 348-1 ;
Abstract
A system performs audio matching to determine the channel to which a television set is tuned. In one embodiment, the system feeds two audio signals to primary and secondary windings of an audio transformer, and employs an output signal taken from a center tap on the primary winding to determine whether the audio signals match. In another embodiment, the system detects transitions of the two audio signals, produces a pulse for each transition, and compares the pulses to determine whether the signals match.