US3187325A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: AT&T Inc
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Filing: 1962-07-02
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Granted: 1965-06-01
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Expires: 1982-07-02
Abstract
No abstract record available.
Inventors
- 👤 Frederick D Waldhauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:44
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
168 words
IN COMBINATION, AN AMPLIFIER HAVING AN INPUT AND AN OUTPUT AND HAVING A GAIN SUBSTANTIALLY GREATER THAN UNITY, A SOURCE OF AN ANALOG SIGNAL CONNECTED TO SAID INPUT, FIRST AND SECOND PARALLEL FEEDBACK PATHS CONNECTED BETWEEN SAID INPUT AND SAID OUTPUT, EACH OF SAID PATHS INCLUDING THE SERIES COMBINATION OF A RESISTOR AND A DIODE, SAID DIODE IN SAID FIRST PATH BEING POLED TO CONDUCT POSITIVE CURRENT FROM SAID INPUT TO SAID OUTPUT, SAID DIODE IN SAID SECOND PATH BEING POLED TO CONDUCT POSITIVE CURRENT FROM SAID OUTPUT TO SAID INPUT, MEANS FOR DERIVING A FIRST SUBSIGNAL FROM THE VOLTAGE EXISTING ACROSS THE RESISTANCE IN SAID FIRST PATH, MEANS FOR DERIVING A SECOND SUBSIGNAL FROM THE VOLTAGE EXISTING ACROSS THE RESISTANCE IN SAID SECOND PATH, MEANS FOR INVERTING THE POLARITY OF ONE OF SAID SUBSIGNALS, AND MEANS FOR COMBINING THE INVERTED SUBSIGNAL WITH THE OTHER OF SAID SUBSIGNALS TO FORM AN OUTPUT SIGNAL HAVING AN AMPLITUDE WHICH IS ACCURATELY RELATED TO THE ABSOLUTE MAGNITUDE OF SAID ANALOG SIGNAL.
Claim 2
Dependent Claim
168 words
IN COMBINATION, AN AMPLIFIER HAVING AN INPUT AND AN OUTPUT AND HAVING A GAIN SUBSTANTIALLY GREATER THAN UNITY, A SOURCE OF AN ANALOG SIGNAL CONNECTED TO SAID INPUT, FIRST AND SECOND PARALLEL FEEDBACK PATHS CONNECTED BETWEEN SAID INPUT AND SAID OUTPUT, EACH OF SAID PATHS INCLUDING THE SERIES COMBINATION OF A RESISTOR AND A DIODE, SAID DIODE IN SAID FIRST PATH BEING POLED TO CONDUCT POSITIVE CURRENT FROM SAID INPUT TO SAID OUTPUT, SAID DIODE IN SAID SECOND PATH BEING POLED TO CONDUCT POSITIVE CURRENT FROM SAID OUTPUT TO SAID INPUT, MEANS FOR DERIVING A FIRST SUBSIGNAL FROM THE VOLTAGE EXISTING ACROSS THE RESISTANCE IN SAID FIRST PATH, MEANS FOR DERIVING A SECOND SUBSIGNAL FROM THE VOLTAGE EXISTING ACROSS THE RESISTANCE IN SAID SECOND PATH, MEANS FOR INVERTING THE POLARITY OF ONE OF SAID SUBSIGNALS, AND MEANS FOR COMBINING THE INVERTED SUBSIGNAL WITH THE OTHER OF SAID SUBSIGNALS TO FORM AN OUTPUT SIGNAL HAVING AN AMPLITUDE WHICH IS ACCURATELY RELATED TO THE ABSOLUTE MAGNITUDE OF SAID ANALOG SIGNAL.
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) | 1968-05-31 | 1968-11-30 | 1969-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-05-31 | 1972-11-30 | 1973-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-05-31 | 1976-11-30 | 1977-06-01 | $7700.00 | Window Closed / Lapsed |