US2825764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cross-control compandor used as echo suppressors
Assignee: AT&T Inc
•
Filing: 1954-02-24
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Granted: 1958-03-04
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Expires: 1974-02-24
Abstract
No abstract record available.
Inventors
- 👤 Paul G Edwards
- 👤 Donald D Robertson
- 👤 Joseph O Smethurst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:57
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/62; H04B1/64; H04B3/00; H04B3/02; H04B3/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2164344A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-03-03 | 1961-09-02 | 1962-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-03-03 | 1965-09-02 | 1966-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-03-03 | 1969-09-02 | 1970-03-04 | $7700.00 | Window Closed / Lapsed |