DMD20/20LBST Universal Satellite Modem
User Interfaces
MN-DMD20-20LBST Revision 14
4–7
DVB: Per EN301-421 & En301-210
Data Rates:
All Rates
Framing Type:
DVB
Scrambler Type:
DVB
Spectrum Mask:
DVB 0.25, 0.35
Closed Net:
All possible combinations allowed, however, a DVB setting
requires the DVB network spec. .
STRAP CODE
{Refer to Strap Code Guide, Appendix H}
The Strap Code is a quick set key that sets many modem
parameters. Consult the strap code guide for available strap
codes. Parameters set by strap code:
Data Rate
Inner Code Rate
Satellite Framing
Scrambler
Drop and Insert
Outer Code Rate (Reed-Solomon)
Modulation
Network Spec
IF (menu)
FREQUENCY (MHz)
{50 – 90 MHz, 100 – 180 MHz, or 950 - 2050 MHz}
Allows the user to enter the Modulator IF Output Frequency of
the modem in 1 Hz increments.
UPLINK FREQ
Displays the output frequency of the BUC also referred to as
Satellite uplink frequency. The user must enter the BUC LO and
OSC SIDE BAND before using this menu. The UPLINK
FREQUENCY is a calculated measurement of both the BUC LO
and OSC SIDE BAND. Once the menus are entered correctly,
the user can control the uplink Frequency from this menu.
POWER (dBm)
{0 to -25 dBm}
Allows the user to enter the Transmitter Power Level.
CARRIER
{ON, OFF, AUTO, VSAT, RTS}
Allows the user to select the carrier type. Refer to Appendix E
for further information.
SPECTRUM
{NORMAL, INVERTED}
Allows the user to invert the direction of rotation for QPSK
Modulation. Normal meets the IESS Specification..
LBST:
Spectral inversion may be required if the BUC LO is
higher in frequency than the BUC output frequency. When BUC
LO is higher than the BUC output frequency, this creates a
spectral inversion and the IF Spectrum must be again inverted to
compensate.