Method of learning the characteristics of a telephone
CA 2319224 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
Dialtone Learning Sequence method of learning the characteristics of any telephone with a 4-wire port interface comprises searching for a CO dialtone detecting, a CO dialtone, selecting receive lines setting the receive channel , sensitivity by comparison with receive level references selecting transmit lines and setting , the transmit channel sensitivity by comparison with a transmit reference signal.
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 May 20, 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.