Ceyear 4051 Series, User Manual

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4. Operating Instruction
4.2 Advanced operation guide
93
 Press 【 BW 】 , [Res BW Auto
Man
] and enter 300 kHz;
 Press
【
Span/X Axis
】
, [Span] and enter 2 MHz.
 Press
【
Trace
】
, [More 1/2
▶
], [Detector
▶
] and [Peak] to switch the detector mode to positive peak. Then
you can see there is only one signal peak on the screen of the analyzer as shown in Fig. 4.8.
Fig. 4.8 Spectrogram when resolution bandwidth (300 kHz) is larger than signal frequency bandwidth
Step 5. change resolution bandwidth to 100 kHz to make it equal to frequency interval of two signals
and reduce video bandwidth to 10 kHz:
 Press 【 BW 】 , [Res BW Auto
Man
] and enter 100kHz;
 Press
【
BW
】
, [Video BW Auto
Man
] and enter 10kHz.
You can clearly distinguish two signals with two independent peaks on top of them, as shown in Fig. 4.9.
Caution
Video bandwidth setting
The video bandwidth is set as 10 kHz in order to show level reduction between two signals in the center of the
screen. For large video bandwidth, video voltage generated by the envelope detector cannot be fully
suppressed. Therefore, additional voltage will be generated in the transition area of two and displayed on the
trace.