Ceyear 4041 Series, Руководство пользователя

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Chapter XI Performance Characteristics Test
158
Fig 11-12 1 dB gain compression test block diagram
1 dB gain compression (50 MHz~4 GHz)
1) Connect the power meter ML2437A and the power sensor MA2445D, and zero them.
2) Connect the test instrument with cable as shown in Fig 11-12. The spectrum analyzer provides a reference
frequency for the two signal sources, and the RF directional coupler is used.
3) After the synthesized signal generator #2 is reset, set its frequency to 2 GHz, the power to 0 dBm, and the
external reference and RF output ON.
4) After the synthesized signal generator #1 is reset, set its frequency to 2.01 GHz, the power to -10 dBm, and
the external reference and RF output OFF.
5) Set the spectrum analyzer as follows (for other settings, the defaults apply):
Center frequency ............................................................................................................................................ 2 GHz
Span ................................................................................................................................................................ 1 kHz
Reference level ........................................................................................................................................... -10 dBm
Logarithmic scale ....................................................................................................................................... 1 dB/div
6) Adjust the output power level of synthesized signal generator #2 to make the peak value of the signal 2-3
divisions below the 4041 reference level.
7) Press
【
Peak
】 【
Marker
】
[Difference Mode] on the 4041, and activate the Difference Marker function.
8) Turn on the RF output of synthesized signal generator #1. Adjust the output power level of synthesized signal
generator #1 until the differential marker reading is close to -1 dB. Turn off the output of synthesized signal
generator #2.
9) Disconnect the output of RF directional coupler from the 4041. Connect it with the power sensor as shown
by the dashed line in Fig 11-12. Set the frequency of the calibration factor of power meter to 2 GHz. At this
time, the reading of power meter is the 1 dB compression point at 50 MHz to 4 GHz band. Record it as test
Synthesized signal
generator#1
BNC cable
RF output
Spectrum Analyzer
Adapter
Adapter
Power
sensor
Directional
coupler
Do not use cables to connect the directional
coupler and the spectrum analyzer
10 MHz IN
10 MHz IN
10 MHz reference output
BNC T connector
Power meter
RF output
Synthesized signal
generator #2
Adapter