Main Assembly; To Load The Default Calibration - HP 54520 Series Service Manual

CAUTION
PON
Main Assembly
The main assembly procedures calibrate and adjust the acquisition system of the instrument.
Calibration involves running the self-calibration. The main assembly adjustments set the
high-frequency pulse response of each channel.
There is no preparation required for calibrating the instrument. However, if it is necessary to
adjust the high-frequency pulse response, the cover must be removed and the disk drive and
power supply moved to allow access to the adjustments on the main assembly. Moving the
power supply requires the use of an extender cable. See "To adjust the high-frequency pulse
response" in this chapter.
To load the default calibration
The default calibration factors are loaded to give a known base for the following hardware and
firmware calibration.
Once the default cals are loaded, all firmware calibrations must be done. This includes all
calibrations in the self cal menu (0, vertical, 1. delay, 2. time null, and 3. logic trigger).
Failure to run the calibrations after loading default cals will result in an uncalibrated
instrument.
Since all calibration must be done in order, firmware calibrations will be presented in the
proper place in the procedures.
Press utility ,thenpress service menu.
Press cal select twice to select cal select 2 (2. default cal).
Set the rear panel Calibration switch to Unprotected (up).
Press start cal. A caution message will be displayed indicating the cal factors will
be overwritten with default values.
Press continue. The status message above the menu will indicate default cal has
been loaded.
Leave the rear panel switch in Unprotected position for firmware calibration
procedures to be performed later in this chapter.
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