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US3519937A Expired / Lapsed US ⏱️ 0.0 years remaining

Quaternary differential-phase-modulated pcm repeater

Assignee: AT&T Inc
•
Filing: 1967-08-08
•
Granted: 1970-07-07
•
Expires: 1987-08-08
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Abstract

No abstract record available.

Inventors

  • 👤 William M Hubbard

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 02:03
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/18; H04L27/20; H04L27/2032; H04L27/2053; H04L27/2057

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US3244986A Cited
US3368038A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1973-07-06 1974-01-05 1974-07-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1977-07-06 1978-01-05 1978-07-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1981-07-06 1982-01-05 1982-07-07 $7700.00 Window Closed / Lapsed

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