Patent US3259841A successfully refreshed from Google Patents.
US3259841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Negative-feedback transistorized electrical continuity tester
Assignee: EECO Inc
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Filing: 1963-05-15
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Granted: 1966-07-05
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Expires: 1983-05-15
Abstract
No abstract record available.
Inventors
- 👤 Donald R Proctor
- 👤 Donald E Sweet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:19
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/50; G01R31/54; G01R31/52
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
162 words
A CIRCUIT FOR PROVIDING AN INDICATION OF ELECTRICAL RESISTANCE COMPRISING FIRST, SECOND AND THIRD TRANSISTORS, EACH HAVING EMITTER, BASE AND COLLECTOR ELECTRODES, THE BASE AND EMITTER OF SAID FIRST TRANSISTOR CONNECTED TO SAID ELECTRICAL RESISTANCE, THE COLLECTOR OF SAID FIRST TRANSISTOR CONNECTED TO THE BASE OF SAID SECOND TRANSISTOR, THE EMITTER OF SAID SECOND TRANSISTOR CONNECTED TO THE BASE OF SAID THIRD TRANSISTOR, A RESISTOR AND AN INDICATING LAMP CONNECTED IN SERIES AND FROM THE BASE OF SAID SECOND TRANSISTOR TO THE COLLECTOR OF SAID THIRD TRANSISTOR, THE COLLECTOR OF SAID SECOND TRANSISTOR CONNECTED TO SAID LAMP, THE EMITTER OF SAID THIRD TRANSISTOR CONNECTED DIRECTLY TO THE BASE OF SAID FIRST TRANSISTOR, MEANS TO ENERGIZE SAID CIRCUIT CONNECTED BETWEEN THE EMITTER OF SAID FIRST TRANSISTOR AND THE JUNCTION CONNECTION BETWEEN SAID RESISTOR AND LAMP; SAID LAMP INDICATING BY ILLUMINATION VALUES OF SAID ELECTRICAL RESISTANCE LESS THAN A GIVEN VALUE, SAID GIVEN VALUE BEING LOW WITH RESPECT TO THE RESISTANCE OF SAID RESISTOR.
Claim 2
Dependent Claim
162 words
A CIRCUIT FOR PROVIDING AN INDICATION OF ELECTRICAL RESISTANCE COMPRISING FIRST, SECOND AND THIRD TRANSISTORS, EACH HAVING EMITTER, BASE AND COLLECTOR ELECTRODES, THE BASE AND EMITTER OF SAID FIRST TRANSISTOR CONNECTED TO SAID ELECTRICAL RESISTANCE, THE COLLECTOR OF SAID FIRST TRANSISTOR CONNECTED TO THE BASE OF SAID SECOND TRANSISTOR, THE EMITTER OF SAID SECOND TRANSISTOR CONNECTED TO THE BASE OF SAID THIRD TRANSISTOR, A RESISTOR AND AN INDICATING LAMP CONNECTED IN SERIES AND FROM THE BASE OF SAID SECOND TRANSISTOR TO THE COLLECTOR OF SAID THIRD TRANSISTOR, THE COLLECTOR OF SAID SECOND TRANSISTOR CONNECTED TO SAID LAMP, THE EMITTER OF SAID THIRD TRANSISTOR CONNECTED DIRECTLY TO THE BASE OF SAID FIRST TRANSISTOR, MEANS TO ENERGIZE SAID CIRCUIT CONNECTED BETWEEN THE EMITTER OF SAID FIRST TRANSISTOR AND THE JUNCTION CONNECTION BETWEEN SAID RESISTOR AND LAMP; SAID LAMP INDICATING BY ILLUMINATION VALUES OF SAID ELECTRICAL RESISTANCE LESS THAN A GIVEN VALUE, SAID GIVEN VALUE BEING LOW WITH RESPECT TO THE RESISTANCE OF SAID RESISTOR.
References Cited (Backward Citations)
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US3025472A
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US2999169A
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US2922148A
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-07-04 | 1970-01-03 | 1970-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-07-04 | 1974-01-03 | 1974-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-07-04 | 1978-01-03 | 1978-07-05 | $7700.00 | Window Closed / Lapsed |