Ceyear 4041 Series, User Manual

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Chapter XI Performance Characteristics Test
154
Fig 11-10 Third-Order Intermodulation Distortion Testing Setup (50 MHz~4 GHz)
Third-order intermodulation distortion (50 MHz~4 GHz)
1) Connect the instrument as shown in Fig 11-10. As shown in the Fig, use the RF directional coupler, and
select the appropriate low pass filter and adapter according to the test frequency. Do not connect the
directional coupler to the spectrum analyzer.
2) Set the frequency of the synthesized signal generator #1 to 900 MHz, the amplitude to 0 dBm, and the RF
output on.
3) After the synthesized signal generator #2 is reset, set its frequency to 900.1 MHz, the amplitude to -110 dBm,
and the RF output off.
4) Connect the power meter ML2437A and the power sensor MA2445D, and zero them. Set the frequency of
the power meter to 900 MHz.
5) Set up the spectrum analyzer as follows (for other settings, the defaults apply):
Center frequency ................................................................................................................................ 900 MHz
Frequency step .................................................................................................................................... 100 kHz
Span ........................................................................................................................................................ 1 kHz
Reference level ................................................................................................................................... -10 dBm
6) Connect the power sensor to the output of the RF directional coupler with an adapter instead of a cable.
7) Adjust the output amplitude of synthesized signal generator #1 so that the reading of power meter is close to
-15 dBm.
8) Remove the power sensor from the RF directional coupler. Use an adapter to connect the RF directional
Spectrum
Analyzer
Synthesized signal
generator #2
Adapter
Sens
or
Adapter
Low pass
filter
3.5 mm cable
10MHz IN
10 MHz output
BNC cable BNC T connector
RF directional
coupler
Power meter
BNC cable
Synthesized signal
generator#1
3.5 mm cable
Low pass filter
Adapter
Adapter
Adapter
Direct connection,
non-cable
10 MHz IN