Analyse Operation Mode, Registered Mode - Promax 25 User Manual

USER'S MANUAL. PROMAX-25
b) QAM CONSTELLATION - IQ
Once the power and BER & MER measurements are obtained, the graphic display
of the Constellation Diagram can be obtained for the DVB-QAM digital signal,
(see appendix B ' Principle of QAM digital modulation. Constellation Diagram').
Once a few seconds have elapsed PROMAX-25 displays a screen like the one
shown in the following figure. This figure features the constellation diagram, the QAM
modulation type, the symbol rate (SR), the error rate generated for the digital signal
(BER), the digital modulation (MER) error ratio metered (see Appendix G 'Measurement
the modulation error ratio (MER) for digital channels') and the quadrants represented (in
this case, graphic representation in four quadrants "ALL").
If the BACK [F3] key is pressed, the measurement functions menu is accessed
again.
Figure 19.- Representation of the Constellation Diagram and BER & MER
When the ALL->Q1 [F2] key is pressed, the transition is made to a single
quadrant Q1: the view is expanded when the ZOOM+ [F1] key is pressed (zoom x4).
Press the ZOOM+ [F1] key to return to the standard display mode.
To switch quadrants, follow these instructions: if the "Q1->Q2" option appears
in the selection box, it means that the Q1 quadrant is represented and when the Q1-
>Q2 [F2] key is pressed, the transition is made to quadrant Q2. If the "Q2->Q3"
appears, then the Q2 quadrant is represented and when the Q2->Q3 [F2] key is
pressed, the transition is made to quadrant Q3. When the "Q3->Q4" option appears it
means that the quadrant Q3 is represented, and when the Q3->Q4 [F2] key is pressed,
the transition will be made to quadrant Q4. Last, if the "Q4->ALL" option appears, it
means that quadrant Q4 is represented and when the Q3->ALL [F2] key is pressed, all
four quadrants will be displayed on screen.

4.2.5.1 ANALYSE operation mode, Registered mode.

In the measurement functions menu, when the registered work mode is
selected, the following page of options appears:
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measurements of a digital channel.
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