Transmit If Output Switch; Transmit If Power; Modulator Power Offset; Modulated If Output Shape - Comtech EF Data SDM-300A Installation And Operation Manual

SDM-300A Satellite Modem
C.2.11

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.
C.2.12

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.
C.2.13

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.
C.2.14

Modulated IF Output Shape

The modem meets the following transmit output spectral mask specifications. The desired
mask is selectable from the front panel or remotely.
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C.2.15

Spurious Emissions

Spurious emissions are measured relative to the power of the modulated carrier. The
measurement is done with the carrier on in continuous mode and modulated by the
correct data/clock signal. Spurious emissions measured in a 3 kHz bandwidth at the
transmit IF output are:
Rev. 4
INTELSAT/EUTELSAT
Closed net (EFData and Comstream)
Closed net (Fairchild compatible)
Closed net (SDM-51, SDM-52)
0 to 500 MHz (-5 to -30 dBm)
0 to 500 MHz (+5 to -20 dBm > 64 kbit/s)
0 to 500 MHz (+5 to -20 dBm < 64 kbit/s)
-55 dBc
-50 dBc
-45 dBc
Specifications
C–9