Telephone line carrier system
CA 1279415 C · Owner: Fitch, Richard Cecil · Inventors: Fitch, Richard Cecil
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A telephone line carrier system comprises a master station and one or more remote stations. Each station is bridged, in a parallel electrical connection onto a wire-, pair that extends from the station to a telephone line switching system. Each station includes multiplexer and demultiplexer equipment for frequency shifting voice and data channels between baseband and RF. Frequency modulation and full duplex transmission are used for voice communication while amplitude modulation and half-duplex transmission are used for data communication. The master station terminates a second telephone line and frequency multiplexes-demultiplexes signals between the second telephone line and the wire-pair …
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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 January 22, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 22, 2008.
- 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.