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Radio call box system

US 2,214,101 A · Inventors: CUMMING LAURENCE G

USPTO PDF

Overview

5 drawing sheets

Every sheet is in the USPTO PDF.

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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.

Why it's free to use

  • Granted September 10, 1940. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by September 10, 1957.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledMay 27, 1938
GrantedSeptember 10, 1940
Term endedSeptember 10, 1957
Application number—
Classification (CPC)H04B1/48 +1 more
Length13 pages

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