Agilent Technologies 54621A, Service Manual

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Calibrating and Adjusting
To perform User Cal
To perform User Cal
Perform self-calibration:
• every 6 months or after 1000 hours of operation.
• if the ambient temperature is >10 °C from the calibration temperature.
• if you want to maximize the measurement accuracy.
The amount of use, environmental conditions, and experience with other
instruments help determine if you need shorter adjustment intervals.
User Cal performs an internal self-alignment routine to optimize the signal path
in the oscilloscope. The routine uses internally generated signals to optimize
circuits that affect channel sensitivity, offset, and trigger parameters.
Disconnect all inputs and allow the oscilloscope to warm up before performing
this procedure.
User Cal should be performed at least once a year, any time the ambient
temperature of the oscilloscope has changed more than 10 °C since the last User
Cal, or after any repair.
Performing User Cal will not invalidate your Certificate of Calibration.
Successful completion of User Cal does not certify this oscilloscope with a
National Institute of Standards and Technology (NIST) calibration.
1
Disconnect all inputs signals from the oscilloscope
2
Set the rear-panel
CALIBRATION
switch to
UNPROTECTED
.
3
Press the Utility key, then press the Service softkey.
4
Begin the Self Cal by pressing the User Cal softkey.
5
When the User Cal is completed, set the rear-panel
CALIBRATION
switch
to
PROTECTED
.
service.book Page 7 Wednesday, December 18, 2002 8:35 AM