Ceyear 4051 Series, Руководство пользователя

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4. Operating Instruction
4.2 Advanced operation guide
104
By this time, the delta marker changes automatically to volt (V) and move the decimal point of the ratio
shown two places to the right to get the distortion percentage. An easy way to determine distortion percentage
is to change the unit to volt. The minimum ratio that can be displayed is 0.01 or 1%.
4.2.2.3 Accurate harmonic measurement
It will be explained below how to measure the harmonic of 1 GHz signals. It takes more steps to measure in
this method, but since measurement is done with smaller frequency span and resolution bandwidth for each
signal, the signal-to-noise ratio is increased and more accurate measurement result will be obtained.
Step 1. connect output of the signal generator to the RF input port of the analyzer.
Step 2. reset the Series Signal Analyzer:
 Press
【
Preset
】
key.
Step 3. set start and stop frequency of the analyzer:
 Press 【 Frequency 】 , [Start Freq] and enter 800 MHz.
 Press [Stop Freq] and enter 2.5 GHz.
As shown in Fig. 4.17, the fundamental wave and the second harmonic are displayed on the screen.
Step 4. set the video frequency to smooth the noise and increase resolution:
 Press
【
BW
】
, [Video BW Auto
Man
] to enable auto off.
Use 【 ↓ 】 key to reduce video bandwidth.
Step 5. use signal tracking to reduce frequency span:
 Press 【 Peak Search 】 to trigger marker and search signal peak.
 Press
【
Frequency
】
and [Signal Track On Off].
 Press 【 Span/X Axis 】 , [Span] and enter 1 MHz.
Step 6. turn off signal tracking:
 Press
【
Frequency
】
and [Signal Track On Off].
Step 7. Move signal peak to top grid line to get the best amplitude measurement accuracy:

Press 【 Marker → 】 and [Marker →
Ref Level
] to obtain an interface as shown in Fig. 4.21.