US3564457A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Start up circuit for adaptive equalizer
Assignee: AT&T Inc
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Filing: 1968-07-18
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Granted: 1971-02-16
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Expires: 1988-07-18
Abstract
Abstract AN ADAPTIVE TRANSVERSAL FILTER EQUALIZER IS DESCRIBED IN WHICH VOLTAGE CONTROLLED ANALOG MULTIPLIERS ARE EMPLOYED AS TAP ATTENUATORS IN CONJUCTION WITH A D.C. OFFSET ADJUSTING LOOP. A SPECIAL START-UP CIRCUIT CONTROLS A STARTUP SEQUENCE SO THAT THE MULTIPLICATION FACTORS OF THE TAP ATTENUATORS CAN BE SET TO ZERO AND THE D.C. OFFSET CAN BE SET TO ZERO IN A NONINTERACTING MANNER.
Inventors
- 👤 Cecil W Farrow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:53
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/03; H04L25/03006; H04L25/03012; H04L25/03114; H04L25/03133
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) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |