High impedance signal detection device
CA 1301385 C · Owner: Schlumberger Industries, Inc. · Inventors: Honick, Ronald J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A low power consuming signal detection device which is attached to a telephone line is provided. The device has means for supplying power within the device with an impedance of at least 5 megohms across the phone line means for, amplifying signals on the line phase-locked-loop signal, sensing means for determining when the frequency of the amplified signal is within a predefined bandwidth and lock, detection means for outputting a control signal when the frequency of the signal is within the predetermined bandwidth for a predetermined period of time. The device may be powered by a telephone central office battery by using means for converting telephone line battery potential to the required …
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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 May 19, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 19, 2009.
- 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.