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Telephone connection between exchanges of the decimal step-by-step type and the nondecimal revertive impulse control type

US 2,467,490 A · Inventors: WILLIAM MCCLEW JOHN et al.

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17 drawing sheets

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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 April 19, 1949. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by April 19, 1966.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledMarch 24, 1945
GrantedApril 19, 1949
Term endedApril 19, 1966
Application number—
Classification (CPC)H04Q3/0016
Length29 pages

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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

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