US3179748A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Balanced demodulator for frequencyshift data signals
Assignee: AT&T Inc
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Filing: 1961-12-19
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Granted: 1965-04-20
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Expires: 1981-12-19
Abstract
No abstract record available.
Inventors
- 👤 Cecil W Farrow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:11
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/10; H04L27/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
36 words
A DEMODULATOR COMPRISING A FREQUENCY DETECTOR RESPONSIVE TO FREQUENCY-SHIFT DATA SIGNALS FOR PRODUCING OUTPUT SIGNAL EXCURSIONS OF DIFFERENT POLARITIES WITH RESPECT TO A PREDETERMINED REFERENCE VOLTAGE LEVEL FOR EACH OF TWO DIFFERENT INPUT SIGNAL FREQUENCIES, AND
Claim 2
Dependent Claim
36 words
A DEMODULATOR COMPRISING A FREQUENCY DETECTOR RESPONSIVE TO FREQUENCY-SHIFT DATA SIGNALS FOR PRODUCING OUTPUT SIGNAL EXCURSIONS OF DIFFERENT POLARITIES WITH RESPECT TO A PREDETERMINED REFERENCE VOLTAGE LEVEL FOR EACH OF TWO DIFFERENT INPUT SIGNAL FREQUENCIES, AND
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-04-19 | 1968-10-19 | 1969-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-04-19 | 1972-10-19 | 1973-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-04-19 | 1976-10-19 | 1977-04-20 | $7700.00 | Window Closed / Lapsed |