Comtech EF Data SDM-300A User Manual
Page 109
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SDM-300A Satellite Modem
Revision 6
Front Panel Operation
MN/SDM300A.IOM
5–15
Upon entry, the current transmitter rate is displayed with the flashing cursor on the first
character of the code rate on line 1. Line 2 displays the data rate. Press [
←] or [→] to make the
selection. To select one of the four pre-assigned rates (A, B, C, or D) press [ENTER] and use
the [
↑] or [↓] to the desired selection and press [ENTER] to execute the change.
To change the data rate using the variable rate selection, press [ENTER] when RX-V is
displayed. A flashing cursor is displayed on the first character of the coding type on line 1.
Press [
←] or [→] to move the flashing cursor, and [↑] or [↓] to increase or decrease the digit at
the flashing cursor. Press [ENTER] to execute the change.
Note: Code Rate 3/4 not compatible with a combination of a CSC Closed Modulator Type and
Sequential Encoder.
Code Rate
Data Rate Range
Non-Turbo Requirements
BPSK 1/2
2.4 to 1250 kbps
{O}QPSK 1/2
4.8 to 2500 kbps
{O}QPSK 3/4
7.2 to 3750 kbps
{O}QPSK 7/8
8.4 to 4375 kbps
8PSK 2/3
64 to 5000 kbps
BPSK 1/1
4.8 to 2500 kbps
{O}QPSK 1/1
9.6 to 5000 kbps
Turbo Requirements
BPSK 21/44
2.4 to 1193.181 kbps
BPSK 5/16
2.4 to 781.25 kbps
{O}QPSK 1/2
4.8 to 2386.363 kbps
{O}QPSK 3/4
7.2 kbps to 3750 kbps
8PSK 3/4
384 to 5000 kbps
Notes:
1. Max Symbol Rate = 2500 ksps.
2. Max Data Rate for Low var. Rate = 512 kbps.
3. OQPSK Option only = OQPSK 1/2, 3/4, or 7/8.