US4538103A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time domain reflectometer apparatus for identifying the location of cable defects
Assignee: J CAPPON & ASSOCIATES Ltd
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Filing: 1982-08-30
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Granted: 1985-08-27
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Expires: 2002-08-30
Abstract
Abstract A time domain reflectometer apparatus for testing a cable and for cooperation with an oscilloscope or other display apparatus which includes structure for generating a first plurality of pulses which are positive going and for generating a second plurality of pulses which are negative going and which are each synchronized with one of the positive going pulses. The apparatus also includes structure for applying at least one of the pluralities of pulses to a cable to be tested, for cooperating with the associated display apparatus, for providing a display of at least reflective pulses from the cable being tested and for bucking the positive going pulses with the negative going pulses to minimize the amplitude displayed of the pulses being supplied to the cable being tested.
Inventors
- 👤 John Cappon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:40
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/08; G01R31/11; G01R27/00; G01R27/02; G01R27/04; G01R27/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
144 words
A time domain reflectometer apparatus for testing a cable and for cooperation with an oscilloscope or other display apparatus which comprises: means for generating a first plurality of pulses which are positive going; means for generating a second plurality of pulses which are negative going and which are each synchronized with one of said positive going pulses; means for applying at least one of said pluralities of pulses to the cable being tested; means for cooperation with the associated display apparatus for providing a display of at least reflected pulses from the cable being tested; means for bucking said positive going pulses with said negative going pulses to minimize the amplitude displayed of the pulses being supplied to the cable being tested; and means for delaying at least some of said pulses for substantially synchronizing said negative going pulses and said positive going pulses.
Claim 2
Dependent Claim
144 words
A time domain reflectometer apparatus for testing a cable and for cooperation with an oscilloscope or other display apparatus which comprises: means for generating a first plurality of pulses which are positive going; means for generating a second plurality of pulses which are negative going and which are each synchronized with one of said positive going pulses; means for applying at least one of said pluralities of pulses to the cable being tested; means for cooperation with the associated display apparatus for providing a display of at least reflected pulses from the cable being tested; means for bucking said positive going pulses with said negative going pulses to minimize the amplitude displayed of the pulses being supplied to the cable being tested; and means for delaying at least some of said pulses for substantially synchronizing said negative going pulses and said positive going pulses.
Claim 3
Dependent Claim
27 words
The apparatus as described in claim 1, wherein: said apparatus includes amplifying means for increasing the amplitude of said pulses being applied to the cable being tested.
Claim 4
Dependent Claim
17 words
The apparatus as described in claim 2, wherein: said amplifying means includes a single transistor amplification stage.
Claim 5
Dependent Claim
17 words
The apparatus as described in claim 3, wherein: said delay means includes at least one AND gate.
Claim 6
Dependent Claim
33 words
The apparatus as described in claim 4, wherein: said means for generating said first plurality of pulses and said means for generating said second plurality of pulses includes at least one monostable multivibrator.
Claim 7
Dependent Claim
28 words
The apparatus as described in claim 1, further including: means for preventing low frequency signals from interfering with the time domain reflectometer display on the associated display apparatus.
Claim 8
Dependent Claim
28 words
The apparatus as described in claim 2, further including: means for preventing low frequency signals from interfering with the time domain reflectometer display on the associated display apparatus.
Claim 9
Dependent Claim
28 words
The apparatus as described in claim 5, further including: means for preventing low frequency signals from interfering with the time domain reflectometer display on the associated display apparatus.
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) | 1988-08-26 | 1989-02-25 | 1989-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-26 | 1993-02-25 | 1993-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-26 | 1997-02-25 | 1997-08-27 | $7700.00 | Window Closed / Lapsed |