Patent · US Expired

Oscilloscope having temperature monitor and recalibration feature to provide long-term high accuracy

US4779039A · kind A · utility

6Cited by
4References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 15, 1987
Grant dateOct 18, 1988
Priority date
Expiry dateOct 15, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R35/002
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.