Patent US3435149A successfully refreshed from Google Patents.
US3435149A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tone generators for delta modulation time division communication switching systems
Assignee: AT&T Inc
•
Filing: 1965-03-17
•
Granted: 1969-03-25
•
Expires: 1985-03-17
Abstract
No abstract record available.
Inventors
- 👤 Hiroshi Inose
- 👤 Zenya Koono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:28
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/444; H04Q1/446; H04Q1/448; H04Q1/4485; H04Q11/00; H04Q11/04
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US3050589A
Cited
US3207851A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-03-24 | 1972-09-23 | 1973-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-03-24 | 1976-09-23 | 1977-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-03-24 | 1980-09-23 | 1981-03-25 | $7700.00 | Window Closed / Lapsed |