US3371312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulse separation circuit
Assignee: Dresser Industries Inc
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Filing: 1964-11-23
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Granted: 1968-02-27
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Expires: 1984-11-23
Abstract
No abstract record available.
Inventors
- 👤 Eric C Hopkinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:10
CPC Classifications
G; G01; G01V; G01V5/00; G01V5/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
155 words
APPARATUS FOR RADIOACTIVITY WELL LOGGING COMPRISING A SUBSURFACE INSTRUMENT; A TRANSFORMERLESS SURFACE UNIT; AND A CABLE SUSPENDING SAID SUBSURFACE INSTRUMENT IN A BOREHOLE TO BE LOGGED; SAID CABLE INCLUDING AT LEAST ONE ELECTRICAL CONDUCTOR CONNECTING SAID SUBSURFACE INSTRUMENT TO SAID SURFACE UNIT; SAID SUBSURFACE INSTRUMENT INCLUDING A SOURCE OF LOW LEVEL NEGATIVE PULSES HAVING POSITIVE OVERSHOOTS, A SOURCE OF LOW LEVEL POSITIVE PULSES HAVING NEGATIVE OVERSHOOTS, AND MEANS FOR IMPRESSING PULSES FROM BOTH OF SAID SOURCES ON THE CONDUCTOR OF SAID CABLE FOR TRANSMISSION TO THE SURFACE OF THE EARTH; SAID TRANSFORMERLESS SURFACE UNIT INCLUDING AN NPN TRANSISTOR, MEANS MAINTAINING SUBSTRANTIALLY ZERO BIAS BETWEEN THE BASE AND EMITTER OF SAID NPN TRANSISTOR, A PNP TRANSISTOR, MEANS MAINTIANING SUBSTANTIALLY ZERO BIAS BETWEEN THE BASE AND EMITTER OF SAID PNP TRANSISTOR MEANS MAINTAINING THE RESPECTIVE EMITTERS OF SAID TRANSISTORS AT A FIXED POTENTIAL, MEANS CONNECTING THE BASES OF SAID TRANSISTORS DIRECTLY TOGETHER AND CAPACITIVELY TO THE CONDUC-
Claim 2
Dependent Claim
155 words
APPARATUS FOR RADIOACTIVITY WELL LOGGING COMPRISING A SUBSURFACE INSTRUMENT; A TRANSFORMERLESS SURFACE UNIT; AND A CABLE SUSPENDING SAID SUBSURFACE INSTRUMENT IN A BOREHOLE TO BE LOGGED; SAID CABLE INCLUDING AT LEAST ONE ELECTRICAL CONDUCTOR CONNECTING SAID SUBSURFACE INSTRUMENT TO SAID SURFACE UNIT; SAID SUBSURFACE INSTRUMENT INCLUDING A SOURCE OF LOW LEVEL NEGATIVE PULSES HAVING POSITIVE OVERSHOOTS, A SOURCE OF LOW LEVEL POSITIVE PULSES HAVING NEGATIVE OVERSHOOTS, AND MEANS FOR IMPRESSING PULSES FROM BOTH OF SAID SOURCES ON THE CONDUCTOR OF SAID CABLE FOR TRANSMISSION TO THE SURFACE OF THE EARTH; SAID TRANSFORMERLESS SURFACE UNIT INCLUDING AN NPN TRANSISTOR, MEANS MAINTAINING SUBSTRANTIALLY ZERO BIAS BETWEEN THE BASE AND EMITTER OF SAID NPN TRANSISTOR, A PNP TRANSISTOR, MEANS MAINTIANING SUBSTANTIALLY ZERO BIAS BETWEEN THE BASE AND EMITTER OF SAID PNP TRANSISTOR MEANS MAINTAINING THE RESPECTIVE EMITTERS OF SAID TRANSISTORS AT A FIXED POTENTIAL, MEANS CONNECTING THE BASES OF SAID TRANSISTORS DIRECTLY TOGETHER AND CAPACITIVELY TO THE CONDUC-
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) | 1971-02-26 | 1971-08-28 | 1972-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-02-26 | 1975-08-28 | 1976-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-02-26 | 1979-08-28 | 1980-02-27 | $7700.00 | Window Closed / Lapsed |