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:
Apr. 15, 1986
Filed:
Sep. 14, 1984
Andrew M Mallinson, Salem, NH (US);
Adrian H Hoodless, Radwell, GB;
Ferranti, PLC, Cheshire, GB;
Abstract
A circuit for converting a TV receiver to operate in accordance with the system associated with received signals, there being either F or F' scan lines in a field, with F<F', includes a counter driven by pulses each representative of one end of a raster scan line, and having M stages, with F and F'<M<2F and 2F'. There is also means to preload the counter selectively with a count of R or R', where (M-2R)=F and (M-2R')=F'. Wide window means detects when a field sync pulse is within a window including the (M-R)th and (M-R') stages, and, in response, the counter, initially, is preloaded with R'. Decision logic means then detects whether a field sync pulse occurs after the Kth stage, with K=M-[R+R']/2, when R' is continued to be preload; or occurs before the Kth stage, when R subsequently is preloaded; and the required TV receiver conversion is completed.