Anritsu FAQs
On my MS272XB how do I determine if a signal I see on the screen is real one, or a spurious response?
An internally generated spurious signal will be at a fixed frequency. Put a marker on the signal and center the signal on the display by using "Marker Freq to Center". Zoom in on the signal by reducing the span. If the span was very wide to begin with, you may need to recenter the signal once when the span becomes significantly narrower. An internally generated spurious signal will stay centered on the display as the span becomes very narrow because it is tied to the instrument's reference oscillator frequency.
