Patent · US Expired

Phase selectable circuit for use in a stereo demodulator

US4637044A · kind A · utility

3Cited by
5References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 16, 1984
Grant dateJan 13, 1987
Priority date
Expiry dateApr 16, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/607
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A circuit has two signal paths. The first path provides a signal with a selected magnitude and phase. The second path selectively provides either no signal or a signal with twice the magnitude and opposite phase with respect to that provided by said first path. The signals of the two paths are combined to provide a signal with a selectable phase. The circuit can be used in a stereo decoder in which an L+R stereo sum signal is combined with an expanded R-L stereo difference signal, provided by an expander also used for a SAP signal, to produce left (L) and right (R) stereo signals so that when the SAP signal is being reproduced, it is of the same phase in both left and right channels.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.