Second-harmonic-wave choking filter
CA 2004398 C · Owner: Nakatani, Tetsuji · Inventors: Nakatani, Tetsuji; Watanabe, Akira
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A strip-type second-harmonic choking filter is constituted such that a main transmission line through which a, fundamental frequency wave is to be transmitted is connected, with a first stub which exhibits a first susceptance value for the fundamental frequency and exhibits a substantially infinite admittance value for a second-harmonic of the fundamental frequency, on a side of said main transmission line; and a second stub which exhibits a second susceptance value which is essentially a conjugate of the first susceptance value for the fundamental frequency and exhibits an infinity or zero admittance value for the second-harmonic frequency at an opposite side of, the transmission line from …
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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
- Filed December 1, 1989 and granted September 14, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 1, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 1, 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
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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.