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HDM 660 T
o
utput
signal
In this menu, you can set the bandwidth, the carrier modulation and the spectral
position of the output signal.
Bx 1A
8MHz QAM64
COFDM-MODE
POS
b
andwidth
of
the
output
signal
To transmit the output signal in the channel range of C21 … C69 a bandwidth
of 8 MHz can be used.
In the channel range of C5 … C12 a bandwidth of
≤
7 MHz must be set.
If frequency setting is selected you can set the bandwidth dependent on the
frequency of the neighbouring-channel.
•
Use the
buttons to set the bandwidth of the output signal
("
5 MHz
" … "
8 MHz
").
C
arrier
modul ation
In this menu item the carrier modulation is set. At this the setting "
QPSK
" corre-
sponds to the lowest and the setting "
QAM64
" to the highest output data rate.
•
Use the
buttons to place the cursor under "
QPSK / QAM…
".
• Set the carrier modulation of the output signal using the
buttons
("
QPSK
", "
QAM16
", "
QAM64
").
i
nverting
the
user
signal
For exceptional cases and "older" digital cable receivers, the spectral posi-
tion of the user signal can be inverted "
NEG
" (negative). The default setting is
"
POS
" (positive).
• Use the
buttons to place the cursor under "
POS
".
• Use the
buttons to set the spectral position to "
NEG
".
• Press the
button.
—> The "Transmission parameters" – "
COFDM-MODE
" menu is activated.
