Ceyear 4051 Series, User Manual

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4. Operating Instruction
4.2 Advanced operation guide
100
Step 7. set attenuator as 0 dB and open interpolation marker:

Press 【 Amplitude/Y Axis 】 , Press 【 Amplitude/Y Axis 】 , [Attenuation ▶ ], [Mech Atten Auto
Man
] and
enter 0 dB.
 Press
【
Peak Search
】
and [MarkerDelt].
Step 8. increase attenuator setting to 10 dB:
 Press
【
Amplitude/Y Axis
】
, [Attenuation
▶
], [Mech Atten Auto
Man
] and enter 10 dB.
Attention should be paid to the reading of delta marker as shown in Fig. 4.16, which is the difference in
distortion when the attenuator setting is 0 and 10 dB. When the attenuator setting is changed, if delta marker
reading is larger than 1 dB, it means certain distortion has been generated by the analyzer. When delta marker
reading is not obvious, the attenuator setting may also be increased.
Fig. 4.16 Set attenuator as 10 dB
The amplitude reading of the delta marker comes from two sources: firstly, positive reading will be displayed
when signal-to-noise ratio is reduced due to increase in RF attenuation; secondly, negative reading will be
shown when the harmonic distortion generated by the analyzer circuit reduces. The larger the reading, the
bigger the error of measurement. In such case, the attenuator setting may be changed to reduce absolute
amplitude of such delta marker reading.
4.2.2.2 Quick harmonic measurement
In this section, harmonic components are measured of a signal with frequency of 1 GHz and power of -10
dBm generated by the signal generator. The 500 MHz calibration signal of the analyzer may also be used, but
the start and stop frequency of the analyzer should be adjusted to match with the signal frequency and its
harmonic.
Step 1. connect output of the signal generator to the RF input port of the analyzer.
Step 2. set the analyzer as spectrum analysis mode and reset: