Keysight N8973B User Manual

64 Keysight NFA Series Noise Figure Analyzers Service Guide
Boot Up and Initialization Troubleshooting
Potential Problems During Boot Process
AIF Xtal Narrow Prefilter Passband Tuning
Algorithm
Adjusts Centering, symmetry and dip of the crystal
prefilter BW set to about 13 kHz
Uses 322.5 MHz Comb Calibrator on the A-IF
A2 Analog IF
AIF Variable Gain Algorithm
The Gain of the Analog IF System is measured and
compared with the ideal gain value. Several conditions
are tested, Dither on/ dither off, A-IF prefilter in and
bypassed, alias filter set wide and narrow.
Uses 322.5 MHz Comb Calibrator on the A-IF
A2 Analog IF
AIF Step Gain Algorithm
Measures the relative gain of the IF for high gain (10 dB)
versus the low gain (0 dB) paths. In normal instrument
operation these two states can be controlled by the user
interface key called “Swept IF Gain”.
Uses the Comb calibrator on the A-IF
A2 Analog IF
LO Power Alignment Algorithm
Measure max LO power then backs off for each band
A13 Front End
Assembly or A15 Front
End Controller
AIF Variable Attenuator Algorithm
Measures the gain in all settings of the A-IF 1 dB step
attenuator. A reference power is measured with atten
4dB
The Comb calibrator on A-IF is used to provide a CW
signal.
A2 Analog IF
Mechanical Attenuator Algorithm
Measures the attenuation of all DC coupled, and one AC
coupled (10 dB) settings of the RF input attenuators.
Reference atten setting is 10 dB
A9 and A10 RF Input
Attenuators
50 MHz calibrator on A16
Reference
Narrow Band Step Cal Alignment Algorithm
Table 2-1 Initial Alignments
Alignment Description Most Probable
Hard ware Failure
Related Hard ware

Keysight N8973B Specifications

General

Brand	Keysight
Model	N8973B
Category	Measuring Instruments
Language	English