GSS PTDT 9200, Инструкция по сборке

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o
utPut signal
In this menu, you can set the bandwidth, the carrier modulation and the spectral
position of the output signal.
Bx 4A
8MHz QAM64 COFDM-MODE
POS
b
andwidth of the outPut signal
To transmit the output signal in the channel range of C21 to C69 a bandwidth
of 8 MHz can be used. In the channel range of C5 to C12 a bandwidth of
≤ 7 MHz must be set. Therefore observe the current output data rate (menu
"Stuffing", page 30). If necessary change the COFDM settings or delete services
by the station filter (page 22).
If frequency setting is selected you can set the bandwidth dependent on the
frequency of the adjacent channel.
Bx 4A
8MHz QAM64 COFDM-MODE
POS
• Use 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 position
of the user signal can be inverted " NEG ". The default setting is " POS ".
• Use to place the cursor under " POS ".
• Use to set the spectral position to " NEG ".
• Press the button.
—> The "Transmission parameters" – " COFDM-MODE " menu is activated.