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PTIS 1000
s
et ting
the
hier arChiCal
modul ation
In order to attain with less field strength a greater range for broadcasters,
with DVB-T so-called "hierarchical modulation" is used. In this process, several
data streams are modulated onto a DVB-T data stream using "Quadrature
Amplitude Modulation" (QAM). The robust "High Priority" data stream (HP)
with a lower data rate is modulated onto the more sensitive "Low Priority" data
stream, which possesses a higher data rate. In good reception conditions, the
receivers can receive both data streams; in poorer reception conditions, only
the "HP" portion.
Bx 4A
Priority:
high
INPUT
• By pressing
set to "
high
" or "
low
"
—> not relevant in the case of standard modulation.
• Press the
button.
—> The "Selecting the input transport stream" – "
INPUT
" menu is acti-
vated when the input signal source "
Tuner A
" without a CA module
installed and "
Tuner B
Programming the input signal source "
Tuner A
" with a CA module
installed the "Setting the PID monitoring" – "
CA
" menu is activated
• Set channel strip "
Tuner B
" in the same way as channel strip "
Tuner A
".
• Press the
button.
—> The "Allocating the IP addresses" – "
IP-OUT 1
" menu is activated.
