Method of learning the characteristics of a telephone
CA 2319706 C · Owner: Hello Direct, Inc. · Inventors: Stelman, Bruce W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A Manual 800 method of learning the characteristics of any telephone with a 4wire port, interface by enabling a Manual 800 mode sending a preamble, attenuating a , transmit channel, attenuating a receive channel enabling switching algorithms and , disabling the Manual 800 mode.
Read the whole patent
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
- Filed March 27, 1997 and granted January 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 27, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 27, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.