Notch filter using helical transmission line and coaxial capacitor
CA 2013983 C · Owner: Petrovic, Branislav · Inventors: Petrovic, Branislav
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A notch filter comprises a helical transmission line enclosed in a conductive cavity, and a high Q capacitor coupled to form a series-resonant circuit. The capacitor is fabricated from a portion of coaxial cable having an outer conductor forming a first plate of the capacitor and an inner conductor forming the second plate of the capacitor. The notch filter is particularly suited for rejecting terrestrial interference in a C-band tuner at an intermediate frequency of about 400 MHz.
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 April 5, 1990 and granted April 26, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 5, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 5, 2012.
- 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.