Patent US3102168A successfully refreshed from Google Patents.
US3102168A
Expired / Lapsed
US
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Supervisory circuits for telephone subscriber's line
Assignee: AT&T Inc
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Filing: 1959-12-24
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Granted: 1963-08-27
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Expires: 1979-12-24
Abstract
No abstract record available.
Inventors
- 👤 Frank P Cirone
- 👤 Terrell N Lowry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:23
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/58
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
108 words
A CIRCUIT FOR SUPERVISING CHANGES-IN-CONDITION IN A SUBSCRIBER SUBSET LOOP OF A TELEPHONE SYSTEM COMPRISING IN COMBINATION A SUBSET LOOP INCLUDING A TELEPHONE SUBSET, A SOURCE OF DIRECT CURRENT FOR ENERGIZING SAID SUBSET, AND FIRST AND SECOND EQUAL IMPEDANCES ON OPPOSITE SIDES OF SAID LOOP CONNECTING SAID SOURCE TO SAID SUBSET; A SERIAL ARRANGEMENT INCLUDING A ZENER DIODE AND A CAPACITOR; MEANS CONNECTING SAID SERIAL ARRANGEMENT TO SAID FIRST AND SAID SECOND IMPENDANCES; MEANS FOR INTERROGATING SAID SERIAL ARRANGEMENT CONNECTED THERETO TO DETERMINE THE CONDUCTION STATE OF SAID SERIAL ARRANGEMENT; AND OUTPUT MEANS CONNECTED TO SAID SERIAL ARRANGEMENT AND RESPONSIVE TO THE DETERMINATION OF THE CONDUCTION STATE THEREOF.
Claim 2
Dependent Claim
108 words
A CIRCUIT FOR SUPERVISING CHANGES-IN-CONDITION IN A SUBSCRIBER SUBSET LOOP OF A TELEPHONE SYSTEM COMPRISING IN COMBINATION A SUBSET LOOP INCLUDING A TELEPHONE SUBSET, A SOURCE OF DIRECT CURRENT FOR ENERGIZING SAID SUBSET, AND FIRST AND SECOND EQUAL IMPEDANCES ON OPPOSITE SIDES OF SAID LOOP CONNECTING SAID SOURCE TO SAID SUBSET; A SERIAL ARRANGEMENT INCLUDING A ZENER DIODE AND A CAPACITOR; MEANS CONNECTING SAID SERIAL ARRANGEMENT TO SAID FIRST AND SAID SECOND IMPENDANCES; MEANS FOR INTERROGATING SAID SERIAL ARRANGEMENT CONNECTED THERETO TO DETERMINE THE CONDUCTION STATE OF SAID SERIAL ARRANGEMENT; AND OUTPUT MEANS CONNECTED TO SAID SERIAL ARRANGEMENT AND RESPONSIVE TO THE DETERMINATION OF THE CONDUCTION STATE THEREOF.
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) | 1966-08-26 | 1967-02-25 | 1967-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-08-26 | 1971-02-25 | 1971-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-08-26 | 1975-02-25 | 1975-08-27 | $7700.00 | Window Closed / Lapsed |