FTE Maximal TWSQ 310 CI, User Manual

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User’s manual · TWSQ 310 CI
- 6 - TWSQ 310 CI version_en_1.0 FTE maximal
4. Modulator configuration
This option allows you to configure the DVB-C modulator that the device has.
- Symbol speed: The available symbol speed ranges from 1 to 6.96 MS/s.
In order to estimate the output symbol speed you have to take into
account the following parameters: input modulation, input symbol
speed, input FEC, output modulation.
For example, for a 8PSK signal with 22000 MS/s and a FEC 2/3, the output
symbol speed should be calculated according to the chosen QAM modulation.
( ) ( )
( ) ( )
QAM symbol nºbit QAM symbol nºbit
PSK symbol nºbit FEC
SYMBOL.IN
V
SYMBOL.OUT
V
⋅
⋅ ⋅
=
⋅
⋅ ⋅ ⋅
=
3
3
2
22000
8
Modulation QPSK 8PSK 16 QAM 32 QAM 64 QAM 128 QAM 256 QAM
Number of bits per
symbol
2 3 4 5 6 7 8
Modulation 16 QAM 32 QAM 64 QAM 128 QAM 256 QAM
Symbol speed (MS/s) 11000 8800 7333 6286 5500
- Spectrum inversion: Activate or deactivate the spectrum inversion in the modulation.
- Modulation: Modulation Format. Options: 16 QAM, 32 QAM, 64 QAM, 128 QAM, 256 QAM.
- Roll-off factor: Roll-off factor reduces the interference between symbols thanks to the raised cosine filtering, the bigger
this value is, the less interference between symbols that will be caused. Typical Value according to rules DVB-C =15 %.
Options: 15 %,13%.
5. Output configuration
In this option you can configure the different parameters of the cable signal.
- Channel standard: It allows you to select the channelling of the cable signal
standards. Options: BG, BG, PAL BG IT, 11, M NTSC, PAL M, PAL N, PAL DK ,
PAL I, BB_AU, DK PAL, L PAL.
- Channel: Output channel of the cable modulation. When you select the output
channel, the field “Frequency (MHz)” will be modified automatically, adapting
itself to the selected channel. Options: C2-C69.
- Frequency (MHz): Output frequency of cable modulation. When you modify
this field, the field “Channel” will be also modified, indicating the channel
equivalent to the selected frequency in the case that this frequency
corresponds to the frequency of a channel. Options: 47-862 MHz.
- Level: Regulation of the output level of the modulated signal. Options: 0-15dB.
- Calibration: Allows the realization of two tests in order to verify the correct
running of the device.
- Output deactivate: It allows activating or deactivating the output of
transmodulator.
- Pure carries output: It allows activating or deactivating the DVB-C
modulation, allowing visualizing the carrier without modulation in the
selected frequency.