Comtech EF Data CDM-710G - Manual (Page 88)

CDM-710G High-Speed Satellite Modem Revision 1
Front Panel Operation MN-CDM710G
6–12
If Tx Modulation Æ Inv is selected:
Tx Spectrum: Normal
Inverted (E)
Select Normal or Invert using the W X arrow keys, then press
ENTER
.
If Tx Modulation Æ α is selected:
Tx (α) Rolloff %: 20 25
35 (E)
The default Rolloff ( α) setting is 20%. Whenever the Mode is changed, (α) reverts to 20%, but
( α) can be modified to 25% or 35% from this menu. Select the value using the
W X arrow keys,
then press
ENTER
.
Tx Modulation Pilot:
Off/On Avg/Peak (E)
Select Off/On or Avg/Peak using the W X arrow keys, then press
ENTER
.
Tx Modulation Pilot:
Off/On Avg/Peak (E)
The default value is Off. Select Off to disable insertion of pilot symbols into the physical layer
frame. Select On to enable insertion of pilot symbols into the physical layer frame. Use the
W X
arrow keys to make the selection, then press
ENTER
.
Tx Modulation Pilot:
Average Peak (E)
The solid cursor indicates the current configuration choice. The CDM-710G automatically
adjusts, but the default value is Average. Select Average or Peak using the
W X arrow keys,
then press
ENTER
.
• Select Average to set the pilots and header to the average power band of the transmitted
constellation (QPSK, 8PSK, 16APSK or 32APSK) per DVB-S2.
• Select Peak to set the pilots and header to the outer ring of the transmitted constellation
(QPSK, 8PSK, 16APSK or 32ASK).
IMPORTANT
Not all commercially available demodulators will function well with the Peak
pilot level.
Tx Frame Size:
Long Short (E)
The default value is Long. When Long is selected, the standard FECFRAME = 64,800 bits is
enabled. If Short is selected, the 16,200 bit frame is enabled. Select Long or Short using the
W X
arrow keys, then press
ENTER
.