Quantum and Evolution Series Installation and Operating Handbook
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useful for identifying transient signals such as intermittent interference, which may be
present.
Signal Spectrum Graph
7.4.2.2 Constellation
Graph
An example signal constellation graph is shown below. This can be used to check for
correct modem operation including issues such as distortion and phase noise. A
persistence mode is also available and allows the user to see the long term effects of
phase noise and interference. Excessive phase noise can cause cycle skips otherwise
seen as unwanted rotations within the constellation.