Comtech EF Data SDM-9000, Инструкция по установке и эксплуатации

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SDM-9000 Satellite Modem Operation
Rev. 4 4–7
4.2.1.1 Configuration Modulator
TX-X CODE_RATE TX Rate Selection. Under the Utility menu, select one of four
(A, B, C, or D) pre-defined TX code/data rate combinations.
On entry, the current TX rate is displayed on line 1. The data
rate is displayed on line 2. Press [
←
] or [
→
] to select one of
four pre-defined rates (A, B, C, or D).
Note: When the TX rate has been programmed, the TX is
automatically turned off to prevent swamping of other
channels. To turn on the TX, use the IF Output function.
TX-IF FREQUENCY Programs the modulator TX frequency between 50 and
180 MHz, in 2.5 kHz steps.
On entry, the current TX frequency is displayed. Press [
←
] or
[
→
] to move the flashing cursor, and [
↑
] or [
↓
] to increment or
decrement the digit at the flashing cursor. Press [ENTER] to
execute the change.
Note: When the TX frequency is changed, the TX is
automatically turned off to prevent the possible swamping of
other channels. To turn the TX on, use the IF Output function.
TX-IF OUTPUT Programs the modulator output on or off.
On entry, the current status of the output is displayed. Press
[
←
] or [
→
] to select ON or OFF. Press [ENTER] to execute the
change.
TX POWER LEVEL Programs the following modulator output power levels:
•
+5 to -20 dBm, in 0.1 dBm steps (no offset)
•
-5.0 to -30.0 dBm (offset)
An offset can be added through the Utility menu to remove
loses or gains in the system.
On entry, the current TX power level is displayed. Press [
↑
] or
[
↓
] to increase or decrease the output power level, in 0.1 dBm
steps. Press [ENTER] to execute the change.
Note: The actual front panel display may be changed in the
power offset utility function. Using this function does not
change the actual output power level.
DIFF. ENCODER Programs the differential encoder on or off.
On entry, the current status of the differential encoder is
displayed. Press [
←
] or [
→
] to select ON or OFF. Press
[ENTER] to execute the change.