Patent · US Expired

Demagnetizing apparatus for erasing signals recorded on concentric tracks

US4821127A · kind A · utility

15Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 20, 1986
Grant dateApr 11, 1989
Priority date
Expiry dateOct 20, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B15/12
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A demagnitizing apparatus erases, track by track, wide-band and high-frequency recorded signals such as signals which are frequency-modulated (FM) with video signals, and thus eliminates the need for a relay to switch a single magnetic head between erasing capability and recording or reproducing capability.

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