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Transmit frequency change time, Phase noise, Transmit if output switch – Comtech EF Data SDM-300L3 User Manual

Page 402: Transmit if power, Modulator power offset

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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.