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Phase modulation type frequency inverter

US 2,169,357 A · Inventors: HANSELL CLARENCE W

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Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

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Why it's free to use

  • Granted August 15, 1939. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by August 15, 1956.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledAugust 31, 1938
GrantedAugust 15, 1939
Term endedAugust 15, 1956
Application number—
Classification (CPC)H04K1/04
Length9 pages

Timeline

Timeline From USPTO dates

193919411943194519471949195119531955Application filedAug 31, 1938Patent grantedAug 15, 1939Term endedAug 15, 1956

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Official USPTO records

Full published documentText and every drawing sheet as a PDF.USPTOFile historyStatus, office actions, notices, fee records and petitions.USPTO Patent CenterPatent Public Search recordSearchable full text and bibliographic data.USPTO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comJustia PatentsFull text, claims and classification.patents.justia.comFreePatentsOnlineFull text and PDF.freepatentsonline.comEspacenetForeign family and legal status.European Patent Office

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