US3178698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Regulator alarm circuit
Assignee: AT&T Inc
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Filing: 1960-09-14
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Granted: 1965-04-13
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Expires: 1980-09-14
Abstract
No abstract record available.
Inventors
- 👤 Robert S Graham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:50
CPC Classifications
H; H03; H03G; H03G1/00; H03G1/0005; H03G1/0035; H03G1/0041; H03G3/00; H03G3/005
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
130 words
IN COMBINATION, AN AMPLIFIER WHICH INCLUDES A THERMISTOR, THE MAGNITUDE OF THE RESISTANCE OF SAID THERMISTOR BEING A PARAMETER OF THE GAIN OF SAID AMPLIFIER, AUTOMATIC GAIN CONTAOL MEANS FOR ALTERING THE RESISTANCE OF SAID THERMISTOR IN RESPONSE TO FLUCTUATIONS IN THE MAGNITUDE OF THE INPUT SIGNAL DELIVERED TO SAID AMPLIFIER, A SOURCE OF A FIRST UNIDIRECTIONAL VOLTAGE OF SUBSTANTIALLY CONSTANT MAGNITUDE, CIRCUIT MEANS FOR PASSING A CURRENT FROM SAID SOURCE THROUGH SAID THERMISTOR TO DEVELOP A SECOND UNIDIRECTIONAL VOLTAGE ACROSS SAID THERMISTOR, THE MAGNITUDE OF SAID SECOND VOLTAGE BEING DIRECTLY RELATED TO THE MAGNITUDE OF THE RESISTANCE OF SAID THERMISTOR, AN ALARM DEVICE, AND MEANS RESPONSIVE TO SAID SECOND VOLTAGE FOR ACTUATING SAID ALRAM DEVICE WHENEVER THE MAGNITUDE OF SAID SECOND VOLTAGE LIES OUTSIDE A PREDETERMINED RANGE OF VALUES.
Claim 2
Dependent Claim
130 words
IN COMBINATION, AN AMPLIFIER WHICH INCLUDES A THERMISTOR, THE MAGNITUDE OF THE RESISTANCE OF SAID THERMISTOR BEING A PARAMETER OF THE GAIN OF SAID AMPLIFIER, AUTOMATIC GAIN CONTAOL MEANS FOR ALTERING THE RESISTANCE OF SAID THERMISTOR IN RESPONSE TO FLUCTUATIONS IN THE MAGNITUDE OF THE INPUT SIGNAL DELIVERED TO SAID AMPLIFIER, A SOURCE OF A FIRST UNIDIRECTIONAL VOLTAGE OF SUBSTANTIALLY CONSTANT MAGNITUDE, CIRCUIT MEANS FOR PASSING A CURRENT FROM SAID SOURCE THROUGH SAID THERMISTOR TO DEVELOP A SECOND UNIDIRECTIONAL VOLTAGE ACROSS SAID THERMISTOR, THE MAGNITUDE OF SAID SECOND VOLTAGE BEING DIRECTLY RELATED TO THE MAGNITUDE OF THE RESISTANCE OF SAID THERMISTOR, AN ALARM DEVICE, AND MEANS RESPONSIVE TO SAID SECOND VOLTAGE FOR ACTUATING SAID ALRAM DEVICE WHENEVER THE MAGNITUDE OF SAID SECOND VOLTAGE LIES OUTSIDE A PREDETERMINED RANGE OF VALUES.
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) | 1968-04-12 | 1968-10-12 | 1969-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-04-12 | 1972-10-12 | 1973-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-04-12 | 1976-10-12 | 1977-04-13 | $7700.00 | Window Closed / Lapsed |