A Digital Velocity and Amplitude Error-Correction System for Component Time Base Correctors

Robert L. Bleidt

This article describes a digital implementation of a velcomp (velocity compensation) and automatic gain control (AGC) system contained in a new component time base corrector design. Techniques of correcting amplitude and phase errors in the demodulated chroma signal through coordinate transformations are developed, and linear interpolation of the correction values calculated for each burst sample through incremental addition is explained. The design tradeoffs and implementation are discussed. Improvements in the playback chroma signal of ¾-in. VCRs, particularly those with track-following heads, are shown.

Print ISSN
Published
1988-11
Content type
Original Research
DOI
10.5594/J06501