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Expired Canadian patentCanada

High speed tape duplicating machine

CA 1314974 C · Owner: Scheffler, Robert G. · Inventors: Scheffler, Robert G.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

A duplicate recording system uses video cassettes for storing master library recordings. On both the recording and the duplicating ends of the system, all signals are buffer stored in an electronic memory while the signals are in a digital form. This buffer storage completely isolates the recording/reproducing steps so that the usual parameter of restraints disappear. For example, the duplication ratio may be any value within the capabilities of the recording/reproducing machines. This isolation eliminates expensive setup procedures heretofore required to switch from one to another duplicating ratio. The buffer storage also provides a more precise transfer with greater fidelity of the …

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

Why it's free to use

  • Granted March 23, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 23, 2010.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledSeptember 25, 1989
GrantedMarch 23, 1993
Term endedMarch 23, 2010
Patent numberCA 1314974 C
Classification (IPC)G11B5/86 +2 more

Timeline

Timeline From CIPO dates

1990199319961999200220052008Application filedSep 25, 1989Patent grantedMarch 23, 1993Term endedMarch 23, 2010

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.