Isdn testing device and method
CA 2000503 C · Owner: Ehrke, Wiley J. · Inventors: Ehrke, Wiley J.; Homkes, Robert J.; Soto, Roy L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A test device is provided for an integrated services digital network (ISDN) system having a Network Terminator (NT) a system/terminal (S/T) interface for coupling the NT to a Terminal Equipment (TE), a transmit line between the S/T interface and the NT to permit a TE coupled to the S/T interface to transmit D channel and B channel information to the NT, and a receive line coupled between the NT and S/T interface to permit a TE coupled to the S/T interface to receive D channel and B channel information from the NT. The test device performs ah initial line connection test to determine if a satisfactory closed loop exists between the NT and the S/T interface connected by the transmit and …
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 October 11, 1989 and granted December 26, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 11, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 11, 2011.
- 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.