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USER'S MANUAL. TV EXPLORER HD +
Noise and impairments cause the demodulator to not always read the symbols
correctly. In this case the hits disperse and create different shapes that at the end will
allow to determine at a glance the type of noise in the signal
Each type of modulation is represented in a different way. A 16-QAM signal is
represented on screen by a total of 16 different zones and a 64-QAM is represented by a
diagram of 64 different areas and so on.
The constellation shows in different colours the density of hits and includes
zooming, scrolling and clearing functions for a better graph representation on screen.
5.15.1 DVB-T/H (COFDM) signal
Activate the UTILITIES menu by pressing the
CONSTELLATION option. Now, on screen will be recorded the hits due to symbols
received during the digital signal transmission.
Figure 45.- Constellation Diagram. DVB-T/H (64 QAM) signal.
By means of the rotary selector
possible to change the frequency, channel or COFDM carrier on tune by the instrument.
The DECAY option sets the visual persistence for symbol impacts on the screen in
a range from 0 (minimum) to 16 (maximum).
First appears the information about the type of modulation DVB-T/H (64 QAM).
Next it is indicated the frequency, the channel and the carrier tuned. It is also indicated
the carrier type (data or pilot). Finally, it shows the status line (similar to the
measurement screen).
12/2011
[22] key, and select the
[1] and the arrow cursors
[6] key, is
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