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US2551681A Expired / Lapsed US ⏱️ 0.0 years remaining

Direct reading loran navigation system

Assignee: RCA Corp
•
Filing: 1949-02-26
•
Granted: 1951-05-08
•
Expires: 1969-02-26
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Abstract

No abstract record available.

Inventors

  • 👤 Jr Howard C Lawrence
  • 👤 Jr Robert R Freas

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-22 23:55
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02; G01S1/08; G01S1/20; G01S1/24; G01S1/245

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-05-07 1954-11-06 1955-05-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-05-07 1958-11-06 1959-05-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-05-07 1962-11-06 1963-05-08 $7700.00 Window Closed / Lapsed

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