UNI-T UTS3000B/A Series User Manual page 33

Track Signal Drift
This chapter will describe how to measure and track signal drift.
Measurement of Frequency Shift of Signal Source
This spectrum analyzer can measure the stability of a signal. Use the maximum hold function to display
and keep the maximum amplitude level and frequency shift of an input signal trace.
1. Connect signal generator to RF IN port of the spectrum analyzer.
2. Set the frequency and amplitude of signal to 300MHz，-20dBm.
3. Set the center frequency, sweep span and reference level：
Press [Default]>Reset
Press [FREQ]>Center Frequency>300MHz，Span>1MHz
Press [AMPT]>Ref Level> -10dBm
4. Place a marker at signal peak and turn on search continuous peak function:
Press [Peak]
5. Use the maximum hold to measure signal drift:
Press [Trace]>Trace Type>Max Hold
When the signal is changing, the maximum hold function is to remain the maximum respond of input
signal. Trace mode is displayed in the annotation on the right of the screen, which includes trace,
trace type and detector.
6. Activate and update trace 2 and then select continuous sweep:
Press [Trace]>Select Trace>Trace 2
Press Trace Type>Clear/Write
Trace 1 stay at the max hold mode to display signal drift.
7. Change the frequency of signal source slowly.
Figure 3-14 Trace Averaging
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