Comtech EF Data CDM-625A, Инструкция по установке и эксплуатации

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CDM-625A Advanced Satellite Modem MN-CDM625A
Front Panel Operation Revision 4
6–13
•
Tx α (Tx Alpha Filter Rolloff Factor) – Use the ▲▼ arrow keys to select the Tx α . Press
ENTER . Valid settings are:
Txα (Tx Alpha rollout Factor) (%) Default
0.05, 0.10, 0.15, 0.25 0.35
The Rx α of the corresponding receiver must match the Tx α – see Sect. 6.2.1.4.1
for details. To summarize:
• Set Rx α = 0.35 if Tx α ≥ 0.25;
• Set Rx α = 0.12 if Txα ≤ 0.20.
6.2.1.3.2 CONFIG: Tx

Freq (Frequency)
Tx-IF Frequency: 0050.0000 MHz
(

)
To edit the Tx-IF Frequency
, use the ◄ ► arrow keys to select a digit, and then use the ▲▼
arrow keys to change that digit. Press ENTER. Valid settings are:
IF Frequency Range Step Size (Increment)
70/140 MHz 50-180 MHz 100 Hz
L-Band (FAST Option) 950-2250 MHz 100 Hz
When you use the ODU menus to configure a BUC lockout frequency, this screen displays a
second line of information:
Tx-IF Frequency: 1750.0000 MHz
(LO:12500 MHz Sat:14250.0000 MHz) (

)
As you edit the IF frequency, the Satellite frequency updates accordingly.
Satellite frequency = LO ± IF frequency
, where the sign ± is determined
by the LO mix parameter:
•
High-sided mix [–] (includes a spectral inversion);
•
Low-sided mix [+].