US4779039A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oscilloscope having temperature monitor and recalibration feature to provide long-term high accuracy
Assignee: Tektronix Inc
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Filing: 1987-10-15
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Granted: 1988-10-18
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Expires: 2007-10-15
Abstract
Abstract Measurement accuracy of an oscilloscope is extended by monitoring the temperature within the oscilloscope, and automatically entering a calibration cycle if the temperature varies by a predetermined amount. A temperature sensor is strategically located within the oscilloscope to sense variations in temperature. A first sensed temperature value is stored. Upper and lower temperature limits representing the maximum permissible deviation from the stored value are calculated. Instantaneous temperature values from the sensor are compared with the stored value, and as long as the instaneous values are with the limits, an indication of extended accuracy is provided. If the instantaneous temperature values vary outside the limits, an automatic calibration cycle is initiated. After calibration, a new temperature value is stored and the monitoring process continues to ensure extended accuracy.
Inventors
- 👤 Clifford E. Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:30
CPC Classifications
G; G01; G01R; G01R35/00; G01R35/002
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
56 words
A method of providing long-term high accuracy of measurements in an oscilloscope, comprising the steps of: providing in said oscilloscope means for automatically calibrating said oscilloscope; monitoring temperature within said oscilloscope; generating a signal if said temperature varies by a predetermined amount; and initiating a calibration cycle by said calibrating means in response to said signal.
Claim 2
Independent Claim
56 words
A method of providing long-term high accuracy of measurements in an oscilloscope, comprising the steps of: providing in said oscilloscope means for automatically calibrating said oscilloscope; monitoring temperature within said oscilloscope; generating a signal if said temperature varies by a predetermined amount; and initiating a calibration cycle by said calibrating means in response to said signal.
Claim 3
Dependent Claim
76 words
A method in accordance with claim 1 wherein said monitoring step comprises: measuring said temperature with a temperature sensor; storing a first temperature value from said temperature sensor in a memory; providing upper and lower temperature limits representative of maximum permissible deviation from said stored temperature; and comparing instantaneous temperature values from said temperature sensor with said stored temperature, wherein said signal is generated if said instantaneous temperature value is outside said upper and lower limits.
Claim 4
Dependent Claim
26 words
A method in accordance with claim 2 further comprising providing an indication of extended accuracy when said instantaneous temperature is within said upper and lower limits.
Claim 5
Dependent Claim
43 words
In an oscilloscope, an apparatus for providing extended measurement accuracy, comprising: means for monitoring temperature within said oscilloscope; means for generating a signal if said temperature varies by a predetermined amount; and means for automatically calibrating said oscilloscope in response to said signal.
Claim 6
Dependent Claim
43 words
In an oscilloscope, an apparatus for providing extended measurement accuracy, comprising: means for monitoring temperature within said oscilloscope; means for generating a signal if said temperature varies by a predetermined amount; and means for automatically calibrating said oscilloscope in response to said signal.
Claim 7
Dependent Claim
78 words
An apparatus in accordance with claim 4 wherein said means for monitoring temperature further comprises: a temperature sensor for measuring said temperature; means for storing a first temperature value; means for providing upper and lower temperature limits representative of maximum permissible deviation from said stored temperature; and means for comparing instantaneous temperature values from said temperature sensor with said stored temperature, wherein said signal is generated if said instantaneous temperature value is outside said upper and lower limits.
Claim 8
Dependent Claim
28 words
An apparatus in accordance with claim 5 further comprising means for providing an indication of extended accuracy when said instantaneous temperature is within said upper and lower limits.
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) | 1991-10-18 | 1992-04-18 | 1992-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-18 | 1996-04-18 | 1996-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-18 | 2000-04-18 | 2000-10-18 | $7700.00 | Window Closed / Lapsed |