Ceyear 4041 Series, User Manual

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Chapter IV Spectrum Analyzer Mode
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hold function of the spectrum analyzer will be applied to observe the amplitude trace and occupied bandwidth of
the drift signal.
2) Measurement of frequency drift of signal generator
The spectrum analyzer can measure the short-term and long-term stability of the signal generator. The spectrum
analyzer with the trace maximum hold function can display the maximum peak amplitude and frequency drift of
the input signal. If you want to measure the signal occupied bandwidth, the trace maximum hold function can be
applied too.
This instance will use the signal tracking function of the spectrum analyzer to keep the drift signal being displayed
at the center position, and use the trace maximum hold function of the spectrum analyzer to capture the drift.
a) Set the signal generator output signal:
Set the signal generator output frequency at 300 MHz and signal amplitude at -20 dBm, connect the signal
generator output to the input port of spectrum analyzer, as shown in Fig 4-1, and activate the RF output.
b) Set the center frequency, span and reference level of the spectrum analyzer:
Press
【
Preset
】
.
Press
【
Freq
】
, [Center Freq], 300 [MHz].
Press [Span], [Span] and 10 [MHz].
Press
【
Ampt
】
, [Ref Level], -10 [dBm].
c) Place the marker at the signal peak position, and activate the signal tracking function:
Press
【
Peak
】
, [Peak Track Off On].
Press
【
Freq
】
, [Signal track Off On].
d) Reduce the span:
Press [Span], [Span], 500 [kHz]. You can see the signal is always kept at the center position.
e) Deactivate the signal tracking function:
Press
【
Freq
】
, [Signal track Off On].
f) Use the maximum hold function to measure the signal drift:
Press the
【
Trace
】
, [Maximum hold].
When the signal changes, the maximum hold function will keep the maximum response to the input signal.
g) Activate the trace 2, and set it to the continuous refresh mode:
Press
【
Trace
】
, [Trace 1 2 3], [Refresh Trace].
h) Change the output frequency of signal generator:
Change the output frequency of signal generator gradually within ±50 kHz by steps of 1 kHz. The display of