Power amplifier having multiple switched stages
CA 2043838 C · Owner: Dickey, Daniel Leo Sr. · Inventors: Weaver, Bryan Alexander; Dickey, Daniel Leo Sr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A power amplifier for a plate load of an AM RF, transmitter includes plural switching stages each powered by a DC source. Each stage is switched from non-sourced to saturation in response to the amplitude of an analog source exceeding a threshold amplitude for the stage; each stage has a different threshold. The thresholds and analog source are arranged so that responses derived between output terminals of the stages change between zero and predetermined amplitudes as the source amplitude changes relative to the thresholds of the different stages. The responses of the different stages are summed. A triangular wave having a small constant maximum amplitude relative to the analog source …
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 June 4, 1991 and granted January 21, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 4, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 4, 2013.
- 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.