Comtech EF Data SDM-300L3, Инструкция по установке и эксплуатации

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SDM-300Ls Satellite Modem Revision 1
Burst Mode Modulator Operation MN/SDM300L3.IOM
B–4
B.2.7 Transmit Frequency Change Time
The time between the end of a remote command and the end of the modem reply for
frequency change and synthesizer lock will be < 200 mS.
B.2.8 Phase Noise
1. The phase noise of the transmit IF output carrier is no worse than:
dBc/Hz Distance from Carrier
-66.0 100 Hz
-76.0 1 kHz
-86.0 10 kHz
-96.0 100 kHz
-96.0 1 MHz
2. Fundamental AC line spurious is -42 dBc or lower.
3. The sum of all the single sideband spurious, from 0 to 0.75 x symbol rate, is
-42 dBc or lower.
B.2.9 Transmit IF Output Switch
When set to off, no signal present at the output is greater than -60 dBm, measured in a
3 kHz bandwidth from 0 to 500 MHz.
B.2.10 Transmit IF Power
The TX-IF power is operator selectable from -5 to -30 dBm, in 0.1 dB steps, with an
accuracy of
±
0.5 dB. The maximum drift due to temperature change over the specified
range is
±
0.5 dB.
As an option the output can be selectable from +5 to -20 dBm, in 0.1 dB steps, with an
accuracy of
±
0.5 dB. The maximum drift due to temperature change over the specified
range is
±
0.5 dB.
B.2.11 Modulator Power Offset
An offset to the displayed IF output power may be entered from -99.0 to +99.0 dB, in
0.1 dB steps.