Dvb-S/S2 Spectrum; Constellation - Telestar SATPLUS 4 Operating Instructions Manual

6. SAT MEASURING RANGE

6.3 DVB-S/S2 spectrum

In addition to the measured values, you can also call up the spectrum of a defined frequency range.
> If you are in satellite measurement mode, press the orange button (SAT) to activate the display of the
frequency spectrum.
or
> In the main menu, switch to the Spectrum item, confirm with OK and select the reception
path on which you want to display the spectrum.
EN
You will now see the entire frequency spectrum of the reception area.
Using the red button (AUDIO), the frequency section (span) can be changed in 3 steps: 300Mhz,
600MHz, Full (entire spectrum).
You can use the navigation cross to move the cursor to any position. A level measurement
(PWR) is carried out at the current position of the cursor.

6.4 Constellation

The constellation diagram is used to display the modulation type.
In the ideal case - interference-free transmission - the data is recognized correctly and appears in the
Constellation diagram as clearly defined points, each exactly in the center of the corresponding quadrant.
However, interference in the transmission channel often means that the receiver cannot correctly interpret
some of the data in the received signal. Therefore, the points do not appear exactly in the theoretical
center of the grid, but a larger scattering of the points becomes visible in the constellation diagram.
The display on the screen is adjusted for each modulation type. For example, a DVB-C 16QAM signal is
displayed on the screen with a total of 16 quadrants, a DVB-C 64 QAM signal with a total of 64 quadrants.
Operating
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