Harmonic ProView 2900 Installation Manual page 108

Chapter 6: Receiver Configuration Modules
Roll-Off
6.2.3.4.
The Roll-Off menu is used for setting the receiver's roll-off factor value according to the roll-
off factor of the transmitted signal.
The Roll-off factor is the factor that is used for the base-band shaping of the transmitted
signal. Set the Roll-Off factor in accordance with the transmitted Roll-Off factor. The following
figure illustrates the Roll-Off screen.
1 1 1 1
2 2 2 2
3 3 3 3
Available options for the Roll-off factor are: 35%. 25%, 20%
FEC Rate
6.2.3.5.
The FEC Rate parameter sets the Forward error correction rate value. The FEC parameter
can be acquired from the satellite transponder information or can be set to automatic. When
in Automatic mode, the ProView 2900 device tries all FEC rates until locking the rate to the
transport stream.
1 1 1 1
2 2 2 2
3 3 3 3
4 4 4 4
5 5 5 5
6 6 6 6
6 6 6 6
The available options are: Automatic, 1/2, 2/3, 3/4, 5/6, 7/8, 8/9
NOTE
If the specific Viterbi rate is not provided, selecting the Automatic option enables the
ProView 2900 to automatically detect the Viterbi rate.
© Harmonic Inc. Manual p/n 101543/Ver 1.0
Roll Roll- - - - off Roll Roll off off off
35% 35% 35% 35%
25% 25% 25% 25%
20% 20% 20% 20%
FEC FEC Rate FEC FEC Rate Rate Rate
AUTOMATIC AUTOMATIC AUTOMATIC AUTOMATIC
1/2 1/2 1/2 1/2
2/3 2/3 2/3 2/3
3/4 3/4 3/4 3/4
5/6 5/6 5/6 5/6
7/8 7/8 7/8 7/8
8 8 8 8/ / / / 9 9 9 9
Satellite Receiver Configuration
6-23 ProView 2900 Series/SW Version 1.94