Keysight 9000 Series Service Manual page 51

Test Limits
Time Scale Limit
Accuracy
Limit is based on years since oscilloscope's last
calibration
TSA = ±(0.4 + 0.5(Years Since Calibration)) ppm
Chapter 3: Testing Performance
Results
Calculated Measured time
TSA Spec scale error
___________ ___________
Performance Test Record
Pass/Fail
___________
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