Ceyear 4051 Series, User Manual

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4. Operating Instruction
4.2 Advanced operation guide
110
 Set the signal generator frequency as 300 MHz and amplitude as -80 dBm; connect RF output of the
signal generator to the input port of the analyzer.
Step 3. set center frequency, frequency span and reference level of the analyzer:

Press 【 Frequency 】 , [Center Freq] and enter 300 MHz.
 Press 【 Span/X Axis 】 , [Span] and enter 1 MHz.
 Press
【
Amplitude/Y Axis
】
, [RefLevel] and enter -40 dBm.
Step 4. use 【 ↓ 】 to reduce resolution bandwidth:
 Press
【
BW
】
, [Res BW] and
【
↓
】
.
As shown in Fig. 4.26, the noise floor reduces and therefore we can see the signal more clearly. Since reduced
resolution bandwidth will result in increase in sweep time, in 4051 Series Signal/Spectrum Analyzer, the
resolution bandwidth is increased or decreased in 10% within the range of 1 Hz - 3 MHz. By choosing a
proper resolution bandwidth, a more delicate balance can be achieved between the sweep time and the
resolution bandwidth.
Fig. 4.26 Reduce resolution bandwidth to measure small signals
4.2.3.3 Measure small signals with average detector and increase in sweep time
When the noise floor of the analyzer covers small signals, average detector can be used and the sweep time
can be increased to smooth the noise so as to increase signal visibility. Longer sweep time will result in better
average noise variance.
Step 1. reset the Series Signal Analyzer:
 Press
【
Preset
】
.
Step 2. Set the signal generator and connect the Series Signal Analyzer: