Comtech EF Data SDM-2020 User Manual
Page 176
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SDM-2020 Satellite Modulator
Revision 7
Remote Control Operation MN/SDM2020M.IOM
A-6
Parameter
Type
Command/Status/
Response
Description of Arguments
Comments
Symbol Rate
Assignment
Command:
Response:
Status:
Response:
Where:
nnnnn = 1/2 (QPSK 1/2) [Code rate], 3/4
(QPSK 3/4), 7/8 (QPSK 7/8), 5/6 (QPSK
5/6), 2/3 (QPSK 2/3), 8P23 (8PSK 2/3),
8P56 (8PSK 5/6), 8P89 (8PSK 8/9),
16Q34 (16QAM 3/4), 16Q78 (16QAM
7/8).
mm.mmmmmm = Symbol rate in MHz.
Note: When using a SMPTE 310M
interface, the data rate is fixed at
19.392658 MHz. While the code rate can
be changed as applicable, an invalid
parameter message will be generated if
any other data rate is input for change.
Set
Modulator
Output
Power Level
Command:
Response:
Status:
Response:
Where: snn.n = -20.0 to +5.0 in 0.1 steps
(nominal range in dBm).
Scrambler
Enable
(Energy
Dispersal)
Command:
Response:
Status:
Response:
Where: xxx = ON or OFF.
Modulator
Spectrum
Rotation
Command:
Response:
Status:
Response:
Where: xxx = NRM (normal spectrum) or
INV (inverted spectrum).
Carrier Only
Mode
Command:
Response:
Status:
Response:
Where: xxxxxx = OFF, DUAL, OFFSET,
or CENTER.
Transmit IF
Output
Power-up
Condition
Command:
Response:
Status:
Response:
Where: xxxx = LAST (last known state)
or OFF (OFF).
This command selects the state that the
TX-IF Output will be at power up.
Set
Modulator
Power Offset
Command:
Response:
Status:
Response:
Where: snn.n = +40.0 to -40.0 in 0.1 dB
increments.
Note: The modulator power offset is
added to the nominal power level.