US3135829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Conference call circuit
Assignee: TDK Micronas GmbH
•
Filing: 1959-10-09
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Granted: 1964-06-02
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Expires: 1979-10-09
Abstract
No abstract record available.
Inventors
- 👤 Richard M Hultberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:20
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/42; H04M3/56
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
A TELEPHONE CONFERENCE CALL CIRCUIT COMPRISING A PLURALITY OF LINES, EACH HAVING SIMILAR ELECTRICAL LOSS CHARACTERISTICS, A PLURALITY OF VOICE CURRENT REPEATERS, EACH PROVIDING A SIGNAL GAIN THAT COMPENSATES FOR SAID LOSS CHARACTERISTICS, MEANS FOR INDIVIDUALLY CONNECTING EACH OF SAID LINES TO A VOICE CURRENT REPEATER, AND MEANS COMPRISING A COMMON BUS FOR REFLECTIVELY COUPLING SAID LINES THROUGH SAID VOICE CURRENT REPEATERS THEREBY TELEPHONICALLY INTERCONNECTING SAID LINES.
Claim 2
Dependent Claim
67 words
A TELEPHONE CONFERENCE CALL CIRCUIT COMPRISING A PLURALITY OF LINES, EACH HAVING SIMILAR ELECTRICAL LOSS CHARACTERISTICS, A PLURALITY OF VOICE CURRENT REPEATERS, EACH PROVIDING A SIGNAL GAIN THAT COMPENSATES FOR SAID LOSS CHARACTERISTICS, MEANS FOR INDIVIDUALLY CONNECTING EACH OF SAID LINES TO A VOICE CURRENT REPEATER, AND MEANS COMPRISING A COMMON BUS FOR REFLECTIVELY COUPLING SAID LINES THROUGH SAID VOICE CURRENT REPEATERS THEREBY TELEPHONICALLY INTERCONNECTING SAID LINES.
References Cited (Backward Citations)
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Cited
US2035536A
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US2449344A
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US2543986A
Cited
US2755445A
Cited
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Cited
US2912503A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-06-02 | 1967-12-02 | 1968-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-02 | 1971-12-02 | 1972-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-02 | 1975-12-02 | 1976-06-02 | $7700.00 | Window Closed / Lapsed |