Patent · US Expired

Magnetic recording and reproduction

US4296447A · kind A · utility

9Cited by
5References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1979
Grant dateOct 20, 1981
Priority date
Expiry dateDec 11, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2005/0018
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic tape recording head comprises a strip of magneto-resistive material whose magnetic field/resistance change characteristic is in the form of two mirror image nonlinear curves starting at the origin of the graph. The strip is energized with a constant current and the voltage across it is fed to two sample and hold circuits. These are respectively triggered by antiphase pulses and the samples from the two sample and hold circuits are fed to the respective inputs of a differential amplifier. A bias conductor alongside the magneto-resistive strip is energized with pulses having the same polarity as, and synchronous with, the sampling pulses so as to bias the strip to predetermined points which are alternately on the positive and negative parts of the graph. The overall effective characteristic is therefore the sum of one part of the graph and the inverted other part, and is substantially linear.

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