Grf-1300a user manual and teaching materials – GW Instek GRF-1300A User Manual
Page 66

GRF-1300A User Manual and Teaching Materials
4. Set up the GSP-730 as follows:
• Center frequency:880MHz
• Span: 5MHz
• Reference level: 0dBm
• RBW: Auto
Step1
F1
0
Step2
Step3
F1
0
Step4
BW
F1
5. Use the Marker function to measure the carrier component of
the AM wave on the spectrum analyzer and the power of the
upper and lower sidebands. Use the oscilloscope to measure the
voltage at TP4 in relation to the position of the potentiometer
(i.e., the modulating amplitude). Draw the spectrum diagram in
Table 5-4.
Step5
Peak
Search
Step6
Marker
0
1
6. Turn the potentiometer counterclockwise to the half-way
mark. Measure the voltage with the oscilloscope. By changing
the output amplitude of the modulating signal, can you observe
any change in the spectrum? Record the experiment in Table 5-4.
7. Turn the potentiometer counterclockwise to decrease the
output voltage. Measure the voltage with the oscilloscope.
Observe any changes in the spectrum of the AM wave and
record it in Table 5-4.
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