Ceyear 4041 Series, User Manual

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Chapter IV Spectrum Analyzer Mode
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At this time, the differential marker unit changes to Volt automatically. A simple method to determine the
distortion percentage is to change the unit to volt. Move the decimal point of displayed ratio of differential marker
rightward by two digits to obtain the distortion percentage. The minimum percentage that can be displayed is 0.01
or 1%.
3) Precision measurement method of harmonic wave
This method involves more steps. However, each signal is measured under minor span and resolution bandwidth.
Therefore, the signal to noise ratio is increased, and the measurement results are more accurate. The description
below instructs how to measure the harmonic wave of 1 GHz signal.
a) Set the signal generator output signal:
Set the signal generator frequency at 1 GHz and signal power at -10 dBm, connect the signal generator output to
the input port of spectrum analyzer, as shown in Fig 4-1, and turn on the RF switch.
b) Set the starting frequency and ending frequency of the spectrum analyzer:
Press
【
Preset
】
key.
Press
【
Freq
】
, [Start Freq], 800 [MHz], [Stop Freq] and 2.5 [GHz].
c) Set the video bandwidth to smooth the noise in order to increase the resolution:
Press
【
BW
】
, [Video BW Auto Man] to activate the manual function.
Reduce the video bandwidth by the key
【 ↓ 】
to decrease the video bandwidth.
d) Reduce the span by using the signal tracking function:
Press
【
Peak
】
to activate the marker to search the signal peak.
Press
【
Freq
】
, [Signal track Off On].
Press
【
Span
】
, 100 [kHz].
e) Deactivate the signal tracking.
Press
【
Freq
】
, [Signal track Off On].
f) Shift the signal peak to top cell of the gridline to obtain the optimal amplitude measurement precision.
Press
【
Peak
】
, [Peak Search], and read the power of peak.
Press
【
Ampt
】
, [Ref Level], and set it to the power of peak, as shown in Fig 4-18.