Comtech EF Data SLM-5650A Installation And Operation Manual page 187

SLM-5650A Satellite Modem
Network Processor (NP) Interface
Enter the Frequency: (70/140 MHz) 52-88, 104-176 MHz (in 100 Hz steps) or (L-Band) 950-2000 MHz (in 100 Hz
steps)
Selection
Normal
Invert
Selection
V.35
Modified-V.35
IBS
Turbo
OM73
Synch
Off
Enter a Power Level from –40 dBm to +10 dBm (in 0.1 dB steps).
Selection
On
RTS
VSAT
Off
When changing Modulation Type the data rate must be set to a rate supported by
the modulation type or the change to the modulation type will not be allowed. Some
choices will only be visible if the modem is set to a compatible mode, or if an option
is installed or enabled
When entering the data rate, the following interactions need to be taken into account.
If the modulation type selected is 8-PSK or 16-QAM the minimum data rate allowed
is 256 kbps. When changing certain parameters like modem type, the data rate will
default to 64 kbps or 256 kbps. The calculated symbol rate is displayed for the user.
This is helpful for determining the occupied bandwidth required for the selected
modulation type, code rate and overhead.
Frequency (MHz)
Description
Used to counteract frequency converters that invert the spectrum
Scrambler (for energy dispersal)
Description
ITU standard
Comtech EF Data Closed Network with Reed Solomon compatible (modified V.35)
Used for IESS-309 and AUPC operation
Synchronous scrambler synchronized to the Turbo block
Linkabit OM-73 modem compatibility mode
Synchronous scrambler synchronized to the Reed-Solomon.
Tx Power Level (dBm)
Description
Request to Send. RTS is an interface signaling control. If enabled, RTS can be used to
control the output state of the modulator. Only available when using either the EIA-530 or
HSSI interface.
VSAT mode ties control of the Transmit Signal to the status of the Receiver. If the receiver
is Locked the Transmitter is Enabled. If the receiver is Unlocked the Transmitter will be
disabled.
8–25
Spectrum
Carrier
Revision 8
MN-SLM5650A