US3299404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detection circuit responsive to pulse duration and frequency
Assignee: AT&T Inc
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Filing: 1962-12-28
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Granted: 1967-01-17
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Expires: 1982-12-28
Abstract
No abstract record available.
Inventors
- 👤 Ronald E Yamarone
- 👤 Herbert M Zydney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:44
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/444; H04Q1/45
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
92 words
IN A CIRCUIT FOR DETECTING A CALL PROGRESS SIGNAL WHICH INCLUDES A TONE INTERVAL OF ALTERNATE PULSES AND A NO-TONE INTERVAL, A TRANSITION DETECTOR OPERATED BY SAID TONE PULSES WHEN THE OCCURRENCE OF THE PULSE TRANSITIONS EXCEED A PREDETERMINED RATE, A PULSE WIDTH DETECTOR OPERATED BY SAID TONE PULSES WHEN THE PULSES EXCEED A PREDETERMINED WIDTH, AND A COINCIDENCE CIRCUIT NORMALLY OPERATED TO ONE OF TWO STATES AND OPERATED TO THE OTHER ONE OF SAID TWO STATES IN RESPONSE TO THE JOINT OPERATION OF SAID PULSE WIDTH DETECTOR AND SAID TRANSITION DETECTOR.
Claim 2
Dependent Claim
92 words
IN A CIRCUIT FOR DETECTING A CALL PROGRESS SIGNAL WHICH INCLUDES A TONE INTERVAL OF ALTERNATE PULSES AND A NO-TONE INTERVAL, A TRANSITION DETECTOR OPERATED BY SAID TONE PULSES WHEN THE OCCURRENCE OF THE PULSE TRANSITIONS EXCEED A PREDETERMINED RATE, A PULSE WIDTH DETECTOR OPERATED BY SAID TONE PULSES WHEN THE PULSES EXCEED A PREDETERMINED WIDTH, AND A COINCIDENCE CIRCUIT NORMALLY OPERATED TO ONE OF TWO STATES AND OPERATED TO THE OTHER ONE OF SAID TWO STATES IN RESPONSE TO THE JOINT OPERATION OF SAID PULSE WIDTH DETECTOR AND SAID TRANSITION DETECTOR.
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) | 1970-01-16 | 1970-07-18 | 1971-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-01-16 | 1974-07-18 | 1975-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-01-16 | 1978-07-18 | 1979-01-17 | $7700.00 | Window Closed / Lapsed |