Station selecting apparatus
CA 2020387 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Usui, Akira
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A station selecting apparatus has a first mixer and a first local oscillation circuit for frequency converting the input signals (television signals) into a first intermediate frequency signal. A second mixer and a second local oscillation circuit convert the first intermediate frequency signal into a second intermediate frequency signal. A variable voltage device capable of varying a direct current fixed voltage in stages provides a signal for controlling the second local oscillator. The minimum potential width of the direct current voltage is set so that the frequency displacement (unit variation amount) of the second local oscillator obtained by the potential difference is smaller than …
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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 July 4, 1990 and granted May 15, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 4, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 4, 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.