Patent · US Expired

Discrimination during reading of data prerecorded in different codes

US4151565A · kind A · utility

5Cited by
3References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 6, 1977
Grant dateApr 24, 1979
Priority date
Expiry dateMay 6, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B20/1419
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A circuit for the decoding during reading of data prerecorded on a magnetic medium comprising a circuit for recognition of the recording code of the data recorded on the support by the recognition of the frequency of an input signal generated during the reading of the support and a frequency generating circuit controlled by the recognition circuit for generating a signal of predetermined frequency for the conversion of the recording code recognized into a binary code. A read-only memory comprising two zones is responsive to the recognition means for generating correcting words applied to a counter for controlling the position of a decoding window generated by a phase locked loop oscillator.

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