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:
May. 13, 1975
H George Pires, Parlin, NJ (US);
Teleglobe Pay TV System Inc., Rego Park, NY (US);
Abstract
Due to unavoidable timing and slope errors in the leading and trailing edges of invert pulses utilized in encoding and decoding of the television signal by inversion of the picture signal portion relative to the synchronizing signal portion, transients are generated. A clamping circuit clamps the television signal to a predetermined reference level for short time intervals around each desired switching time instant. The time intervals are sufficiently long to include the maximum possible variation in the actual timing of the switching time instants. A grey level is thus inserted at the encoder. At the decoder, a clamping circuit clamps the television signal to ground potential during the grey level intervals thereby balancing the DC components of the signal portions.