US3431369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical transmission testing system having test results transmitted in pulse width modulation form
Assignee: AT&T Inc
•
Filing: 1966-03-29
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Granted: 1969-03-04
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Expires: 1986-03-29
Abstract
No abstract record available.
Inventors
- 👤 George E Mclaughlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:11
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/32
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2721235A
Cited
US2819354A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-03-03 | 1972-09-02 | 1973-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-03-03 | 1976-09-02 | 1977-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-03-03 | 1980-09-02 | 1981-03-04 | $7700.00 | Window Closed / Lapsed |