Comtech EF Data SDM-300L3 - Manual (Page 204)

SDM-300L3 Satellite Modem Revision 1
Modem Types MN/SDM300L3.IOM
5–4
5.4 D&I Operation
To operate the modem in the Drop & Insert configuration, the following cards must be installed
in the modem:
• Overhead G.703/IDR/IBS/ASYNC/AUPC/D&I card
• 50-pin D relay adapter card
The D&I option is a FAST feature that must be enabled using the front panel and the Utility
Modem Type menu. Table A-5 lists the parameters that are accessible once the D&I modem type
is enabled.
T ABLE 5-4. D&I P ARAMETER S ETTINGS
Parameter Front Panel Settings Reference Manual
Modem Type D&I Utility - Modem Type
TX Data/Code Rate TX-V, QPSK 1/2 (NX64)
TX-IF Output ON Configuration - Demodulator
RX Data/Code Rate RX-V, QPSK 1/2 (NX64)
Table 5-3 Configuration - Demodulator
TX Clock Source TX Terrestrial Configuration - Interface
Buffer Clock Source Insert Clock Configuration - Interface
TX Coding Format HDB3 Configuration - Interface
RX Coding Format HDB3 Configuration - Interface
Drop Format E1CCS/E1CAS (E1) Configuration - Interface
Insert Format E1CCS/E1CAS (E1) Configuration - Interface
In D&I operation, the transmit data rate is a fractional portion of the trunk T1 or E1 terrestrial
input. The N stands for the number of 64 kbps time slots available for transmission. Table A-6
shows the allowable TX data rates for D&I with the corresponding number of time slots available
for each data rate.
T ABLE 5-5. N X 64 C HART
Time Slots TX Data Rate Time Slots TX Data Rate
1 64 kbps 10 640 kbps
2 128 kbps 12 768 kbps
3 192 kbps 15 960 kbps
4 256 kbps 16 1024 kbps
5 320 kbps 20 1280 kbps
6 384 kbps 24 1536 kbps
8 512 kbps 30 1920 kbps