Speakerphone control circuit
CA 1207928 A · Owner: American Telephone And Telegraph Company · Inventors: Munson, Verne E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract There is disclosed a speakerphone circuit employing precision peak detectors in which the processing of talk down signals and switch guard signals is partitioned in order to accurately control complementary switched gain in the transmit and receive channels to achieve improved sensitivity to talk down switching action by setting a low switching threshold.
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
- Granted July 15, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 15, 2003.
- 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.