Ceyear 4051 Series, Руководство пользователя

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4. Operating Instruction
4.2 Advanced operation guide
121
Fig. 4.35 Measure AM signal modulation speed with demodulation waveform
4.2.6.4 Measure AM modulation depth with demodulation waveform
In this section, we explain how to use the analyzer as a fixed-tuned (time domain) reciever to measure AM
signal modulation depth with the measurement result expressed in percentage.
Step 1. connect output of the signal generator to the RF input port of the analyzer:
 Set the signal generator with an AM signal with output carrier of 300 MHz, amplitude of -10 dBm,
modulation signal of 1 kHz and AM depth of 80%.
Step 2. reset the analyzer and set center frequency, frequency span and sweep time:
 Press
【
Preset
】
.
 Press 【 Frequency 】 , [Center Freq] and enter 300MHz.
 Press
【
Span/X Axis
】
, [Span] and enter 500kHz.
 Press
【
BW
】
, [Res BW Auto
Man
] and enter 30kHz;
 Press 【 Sweep 】 , [Sweep Time Auto
Man
] and enter 20 ms.
Step 3. set Y axis scale unit as volt:
 Press
【
Amplitude/Y Axis
】
, [MORE 1/2
▶
], [Y Axis Unit
▶
] and [V].
Step 4. place the signal peak near the reference level:
 Press 【 Amplitude/Y Axis 】 , [RefLevel] and turn the knob to adjust the reference level.
Step 5. change Y axis display scale to linear scale:
 Press
【
Amplitude/Y Axis
】
and [Scale Type Log Line].
Step 6. set the analyzer as zero frequency span for time domain measurement: