Patent Yard Sign in
Expired Australian patentAustralia

Method and apparatus employing audio frequency offset extraction and floating-point conversion for digitally encoding and decoding high-fidelity audio signals

AU 1987078947 · Applicant: Frederiksen & Shu Laboratories Inc

AusPat record

Overview

Drawings and full text

Its specification, documents and status are on IP Australia's AusPat.

Open the AusPat record

Read the whole patent

Listed from its IP Australia record in Patent Yard's archive of Australian patents past their term. Its claims, description and drawings are in the AusPat record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed September 24, 1987 and granted October 3, 1990. An Australian standard patent lasts 20 years from its date of patent, which is at most a year after this filing, so its term ended by September 24, 2008.
  • A pharmaceutical extension adds at most five years, so even that would have ended by September 24, 2013.
  • We check Australian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledSeptember 24, 1987
GrantedOctober 3, 1990
Term ended bySeptember 24, 2008
Application numberAU 1987078947
Classification (IPC)G11B20/10 +2 more

Timeline

Timeline From IP Australia dates

1988199119941997200020032006Application filedSep 24, 1987Patent grantedOct 3, 1990Term ended bySep 24, 2008

Sources & verification

Everything on this page comes from the IP Australia record linked above. Data from IP Australia's IPGOD, licensed under CC BY 2.5 AU.