HP 8590 E-Series User Manual page 46

Improving Accuracy with Self-Calibration Routines
Data from the self-calibration routine is necessary for spectrum analyzer operation. Executing
the self-calibration routine regularly ensures that the spectrum analyzer is using current
calibration data that improves the spectrum analyzer frequency and amplitude accuracy. Press
the ICAL) key to view the self-calibration routine menus. The last softkey on this menu, labeled
More 1 of 4 , provides access to additional self-calibration functions. For more detailed
information on the self-calibration softkeys, refer to Chapter 7.
The self-calibration routines add correction factors to internal circuitry. The addition of the
correction factors is required to meet frequency and amplitude specifications.
When the correction factors are added to internal circuitry, CORR (corrected) appears on the left
side of the screen.
Warm-Up Time
In order for the spectrum analyzer to meet its specifications, allow the spectrum analyzer
to warm up for 30 minutes after being turned on before attempting to make any calibrated
measurements. Be sure to calibrate the spectrum analyzer only after it has met operating
temperature conditions.
The spectrum analyzer frequency and amplitude self-calibration routines are initiated by the
CAL FREQ L AMPTD softkey in the menu located under the ICAL] key.
1. To calibrate the instrument, connect the spectrum analyzer CAL OUT to the INPUT 5On
connector with an appropriate cable.
Note
A low-loss cable should be used for accurate calibration. Use the 500 cable
shipped with the spectrum analyzer. (Instruments equipped with Option 001 or
2. On the spectrum analyzer, press (CAL) and CAL FREQ & AMPTD
be displayed if CAL OUT is not connected to the spectrum analyzer input. The frequency
and amplitude self-calibration functions take approximately 5 minutes to finish (9 minutes
with Option 130), at which time the internal adjustment data is in working RAM.
3. To save this
data in the area of spectrum analyzer memory that is saved when the spectrum
analyzer is turned off, press CAL STORE .
Note
To interrupt the calibration routines started by CAL FREQ , CAL AMPTD , or
CAL FREQ & AMPTD , press (-1, (CAL), More 1 of 4 , and CAL FETCH.
CAL FETCH retrieves the previous correction factors. Improperly interrupting
the self-calibration routines may result in corrupt correction factors. (If this
occurs, press CAL FREQ t AMPTD to rerun the frequency and amplitude
self-calibration routines.)
The frequency and amplitude self-calibration functions can be done separately by using the
CAL FREQ or CAL AMPTD softkeys instead of CAL FREQ & AMPTD .
2-16 Getting Started
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