Ceyear 4051 Series, Руководство пользователя

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8. Specifications and test methods
8.5 Performance characteristics test
661
7) Execute Continuous Measurement Off, record current 3 dB bandwidth marker difference reading Δf-3 dB
in the column ―3 dB bandwidth measurement value‖ in B6 of the 4051 Auxiliary Form.
8) Set the 4051 analyzer according to the resolution bandwidth listed in B6 of the 4051 Auxiliary Form, set
the frequency span as approximately 2 times of the resolution bandwidth and repeat step 6 ~ 7.
9) Reset the 4051 analyzer, set its center frequency as 500 MHz, the frequency span as 100 MHz, the
reference level as 0 dBm, the amplitude scale as 10 dB, the resolution bandwidth as 10 MHz, VBW/RBW
as 0.1 and the sweep type as sweep frequency and then execute Peak Search.
10) Adjust the output power of the synthesized signal generator until the 4051 signal peak amplitude reading
is closest to 0 dBm. Turn on NdB bandwidth measurement function and change N value to 60.
11) Execute Continuous Measurement On, Peak Search and Marker to Center to move the signal peak to the
center of the screen.
12) Execute Continuous Measurement Off, record current 60 dB bandwidth marker difference reading Δf-60
dB in the column ―60 dB bandwidth measurement value‖ in B6 of the 4051 Auxiliary Form.
13) Set the 4051 analyzer according to the resolution bandwidth listed in B6 of the 4051 Auxiliary Form, set
the frequency span as approximately 5 ~ 10 times of the resolution bandwidth and repeat step 11 ~ 12.
d) Test records and data processing
14) Calculate the resolution bandwidth accuracy δ according to the formula (12) and record it in the 4051
Record Sheet.
Where Δf
-3dB
refers to 3 dB bandwidth measurement value of the 4051 analyzer (Hz);
RBW refers to the nominal value of the 4051 analyzer resolution bandwidth (Hz).
15) Calculate the resolution bandwidth selectivity S according to the formula (13) and record it in the 4051
Record Sheet.
Where Δf
-60dB
refers to 60 dB bandwidth measurement value of the 4051 analyzer (Hz);
Δf
-3dB
refers to 3 dB bandwidth measurement value of the 4051 analyzer (Hz).
8.5.1.1.11 Maximum analysis bandwidth
a) Test item s
The nominal value of maximum analysis bandwidth of the 4051 analyzer is 10 MHz, option H38A is 40 MHz
and option H38B is 200 MHz. Set the 4051 analyzer as I/Q analysis mode for two synthesized signal
generators of stable frequency to provide constant amplitude signals for the 4051 analyzer at the same time;
change frequencies of two signals within the demodulation bandwidth successively until amplitude difference
of all signals does not exceed 3 dB, which means the maximum analysis bandwidth is met.
b) Testing block diagram and testing instrument and equipment
E8257D/1464 is recommended for synthesized signal generator #1.
E8257D/1464 is recommended as the synthesized signal generator#2.
c) Test procedure
1) Connect the tested instrument as shown in Fig. 8.6 and reset the 4051 analyzer.