Ceyear 4051 Series, Руководство пользователя

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8. Specifications and test methods
8.5 Performance characteristics test
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such two errors should fall within the range of reference level switching error, otherwise, the they will be
considered as noncompliant.
11) Calculate the reference level switching error ΔA according to the formula (22) and record it in the 4051
Record Sheet.
8.5.1.2.9 Display scale fidelity
a) Test items
The display scale fidelity is the error between the vertical scale on the screen of the signal/spectrum analyzer
and its theoretical value. It is used to assess scale accuracy of the 4051 analyzer.
When testing fidelity with 10 dB/division, the resolution bandwidth of the schematic diagram is 1 kHz and the
input signal start amplitude is set as 0 dBm reference level. When the signal amplitude is reduced, the
displayed signal amplitude is compared with the reference level. The 4051 analyzer provides 10 MHz
frequency reference for the signal generator.
b) Test equipment
Synthesized signal generator (E8257D/1464 is recommended)
84906L is recommended for the standard attenuator.
11713C is recommended for the attenuator drive.
c) Test steps
1) Connect the instrument as shown in Fig. 8.12, reset the 4051 analyzer and set it to provide frequency
reference for the signal generator. Set the frequency of the signal generator as 30.02 MHz and the output
amplitude as 0 dBm.
2) Use 11713C to reduce the 84906L standard attenuator to 0 dB attenuation. Record the standard value of
the standard attenuator at 30.02 MHz frequency point in the 4051 Auxiliary Form.
3) Reset the 4051 analyzer, execute all calibrations, wait until all calibrations are done and set the following
parameter:
Center frequency: 30.02MHz
Span: 10kHz
Resolution bandwidth: 1kHz
Video bandwidth: 30Hz
4) Adjust the output amplitude of the synthesized signal generator to display the signal peak at the reference
level.
5) Execute Peak Search and Marker Delta.
6) Use 11713C to reduce the 84906L standard attenuator to 10 dB attenuation.
7) Set and execute Continuous Measurement Off and wait for the sweep operation to complete.
8) Record the Marker Delta amplitude reading ΔL of the 4051 analyzer in B12 of the 4051 Auxiliary Form.
9) Turn on Average when the reading fluctuation of the Marker Delta of the signal/spectrum analyzer
exceeds relevant requirement.
10) Repeat step 6 ~ 9 according to the set value of the standard attenuator in B12 of the 4051 Auxiliary Form.
11) Calculate the relevant display scale error ΔAV according to the formula (23) and record it in the 4051
Record Sheet: