Ceyear 4041 Series, User Manual

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Chapter XI Performance Characteristics Test
146
on the noise marker function.
5) Set the RBW and VBW according to Table 11-3, turn on the averaging function, and then conduct 10
averaging operations.
6) Record the differential marker amplitude at the corresponding measurement item in the 4041 Series
Spectrum Analyzer Record Sheet as the sideband noise at the offset point of +10 kHz.
7) Press
【
Marker
】
at -10 [kHz] on the spectrum analyzer. Record the differential marker amplitude at the
corresponding test item in the 4041 Series Spectrum Analyzer Record Sheet as the sideband noise at the
offset of -10 kHz.
8) Set the spectrum analyzer according to Table 11-3 to test the single sideband noise at the offset of ±100 kHz,
±1 MHz and ±10 MHz, and record the differential marker amplitude at the corresponding item in the 4041
Series Spectrum Analyzer Record Sheet. In case of the spurious response at the frequency offset, avoid this
spurious response when reading the marker value during the test.
Table 11-3 Settings of sideband noise measurement
Offset frequency Δf
Span Resolution Bandwidth VBW and average
±10 kHz 30 kHz 300 Hz VBW 30 Hz, averaging function
On
±100 kHz 300 kHz 3 kHz VBW 300 Hz, averaging function
On
±1 MHz 2.2 MHz 10 kHz VBW 1 kHz, averaging function
On
±10 MHz 25 MHz 100 kHz VBW 10 kHz, averaging function
On
11.8 Displayed average noise level
Description: The displayed average noise level refers to the background noise observed by the spectrum analyzer
itself in the absence of external noise or signal.
The input end of the spectrum analyzer is connected with a 50

matcher, and the normalized noise value observed
when the input attenuation value is set to 0 dB is the test value of displayed average noise level.
A) Testing equipment
50Ω Matcher 70508
b) Test steps
1) Connect the 50

matcher to the RF input port of the spectrum analyzer as shown in Fig 11-8.