Comtech EF Data CDM-760, Installation And Operation Manual

Page: 98 / 441

Front Panel Operation Revision 4
CDM-760 Advanced High-Speed Trunking Modem MN-CDM760
6–9
Network Spec QPSK 8PSK 16APSK 32APSK 64APSK
DVB-S2-EB2
1/2, 8/15, 17/30,
3/5, 19/30, 2/3,
127/180, 3/4, 4/5,
5/6, 31/36, 8/9,
9/10
17/30, 3/5, 19/30,
2/3, 127/180, 3/4,
4/5, 5/6, 31/36, 8/9,
9/10
19/30, 2/3,
127/180, 3/4, 4/5,
5/6, 31/36, 8/9,
9/10
127/180, 3/4, 4/5,
5/6, 31/36, 8/9,
9/10
4/5, 5/6, 31/36, 8/9,
9/10
DVB-S2X
¼, 13/45, 1/3, 2/5,
9/20, ½, 11/20,
3/5, 2/3, 3/4, 4/5,
5/6, 8/9, 9/10
5/9L, 26/45L, 3/5,
23/36, 2/3, 25/36,
13/18, 3/4, 5/6, 8/9,
9/10
1/2L, 5/9L, 26/45,
3/5, 3/5L, 28/45,
23/36, 2/3L, 2/3,
25/36, 13/18, 3/4,
7/9, 4/5, 5/6, 77/90,
8/9, 9/10
2/3L, 32/45, 11/15,
3/4, 7/9, 4/5, 5/6,
8/9, 9/10
32/45L, 11/15, 7/9,
4/5, 5/6
ACM Auto Auto Auto Auto Auto
(CONFIG: Tx) Mod

Frame
You should consider the use of Short Block Framing only when there is a concern about
data latency. In all other circumstances, Normal Block Framing should be used. See
Figure C-4 Single Hop Latency in Appendix G. ADAPTIVE CODING AND MODULATION
(ACM) OPTION for an illustration of how Normal and Short Block Framing affects
overall system latency.
Use the  arrow keys to select Normal (default) or Short Block . Press ENTER .
Note the following:
Setting FECFRAME Bits Enabled Remarks
Normal 64,800 This is the default (standard) setting.
Short 16,200
Short Block Framing performs 0.2 db to 0.3 db worse in terms of
required Es/No for all ModCods.
(CONFIG: Tx) Mod

Pilot
Use the

arrow keys to select Pilots as On or Off , then press ENTER :
• On
enables the insertion of pilot symbols into the physical layer frame
• Off
disables this insertion
When Pilot is On , pilots are always placed at the average power point of any
constellation.