Ceyear 4051 Series, Руководство пользователя

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8. Specifications and test methods
8.5 Performance characteristics test
660
Where, ΔT refers to the time difference between the second peak and the tenth peak;
T refers to the set sweep time of 4051 analyzer.
15) Determine values in results of all test items in B5 of the 4051 Auxiliary Form. If all results fall within the
range of error, the absolute maximum error in the result from step 9 should be recorded in the 4051
Record Sheet. Otherwise, the record will be considered not compliant with relevant requirements.
8.5.1.1.9 Range of sweep points
a) Test items
Sweep points are used to set the number of trace data that is required to be captured by the signal/spectrum
analyzer during one measurement. If the sweep points are added, the span corresponding to each trace datum
is narrower, the measured results are more stable and the frequency readout accuracy is higher.
Sweep points are guaranteed during design and production by the manufacturer of the analyzer and can be
checked via the sweep points setting.
b) Test procedure
1) Reset the 4051 analyzer, enter the sweep menu and set the sweep points from 101 to 300001.
2) Determine measurement values according to the requirements in Section 3.12.1.9. If all results fall within
the range of error, ―compliant‖ should be noted in the 4051 Record Sheet, otherwise it should be
considered as noncompliant.
8.5.1.1.10 Resolution bandwidth
a) Test items
The frequency resolution refers to the capacity of the signal/spectrum analyzer to distinguish the smallest
constant amplitude signal.
The signal generator produces standard sine waves. The change of the signal generator frequency can be
considered as equivalent to the change of the IF filter frequency; the measurement of the amplitude response
of signals of different frequencies in fixed frequency points of the signal analyzer can be considered as
equivalent to the measurement of the shape of IF filter (including 3 dB bandwidth and rectangle coefficient).
b) Test equipment
E8257D/1464 is recommended as the synthesized signal generator.
c) Test procedure
1) Connect the instrument as shown in Fig. 4. The 4051 analyzer provides the frequency reference for the
synthesized signal generator.
2) Set the synthesized signal generator as follows: frequency as 500 MHz, power as -2 dBm, power step as 1
dBm and IF output on.
3) Reset the 4051 analyzer, complete all calibrations, turn on NdB bandwidth measurement function and
change N value to 3.01.
4) Set the center frequency of 4051 as 500 MHz, the frequency span as 20 MHz, the amplitude scale as 1 dB,
the resolution bandwidth as 10 MHz and VBW/RBW as 0.1.
5) Adjust the output amplitude of the synthesized signal generator to display the signal peak 2 ~ 3 divisions
below the reference level ( 2 dB ~ 3 dB).
6) Execute Continuous Measurement On, Peak Search and Marker to Center to move the signal peak to the
center of the screen.