Comtech EF Data CDM-425, Инструкция по установке и эксплуатации

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CDM-425 Advanced Satellite Modem
Revision 0
Front Panel Operation 6–49 MN-CDM-425
6.2.1.11.1 CONFIG: Mask

AIS
AIS: Tx-Terr-AIS = Masked (Active,Mask)
Rx-Sat-AIS = Active (

)
Use the
◄ ►
arrow keys to select Tx-Terr-AIS or Rx-Sat-AIS , and then use the
▲▼ arrow keys
to select either as Active or Masked . Press ENTER .
Note that:
•
When you select Tx-Terr-AIS as Active , the modem generates a fault whenever the
modulator senses that the ‘all ones’ condition is present in the terrestrial data.
•
When you select Rx-Sat-AIS as Active , the modem generates a fault whenever the
demodulator senses that the ‘all ones’ condition is present in the receive data.
•
Typical for either, when you select AIS as Masked , the modem generates no alarms.
6.2.1.11.2 CONFIG: Mask

Buffer/Ref
Buffer Slip Alarm = Active (Active,Mask)
Reference Alarms = Active (

)
Use the
◄ ►
arrow keys to select Buffer Slip Alarm or Reference Alarms . Then, typical for
either choice, use the
▲▼ arrow keys to select
Active or Masked .
When you select the Buffer Slip Alarm as Active , the modem generates a Buffer Slip Rx Fault
whenever the Rx circuitry senses that the buffer is either underflowing or overflowing. Press
ENTER .
6.2.1.11.3 CONFIG: Mask

RxIF
RxIF Alarms: AGC=Active (Active,Mask)
EbNo=Masked (

)
Use the
◄ ►
arrow keys to select AGC or EbNo . Then, typical for either choice, use the
▲▼
arrow keys to select the alarms as Active or Masked . Press ENTER .
Note that:
•
Selecting the AGC Rx IF Alarm as Active generates an AGC fault whenever the receive
signal level exceeds –20 dBm (for the desired carrier).
•
Selecting the EbNo Rx IF Alarm as Active generates an Eb/No fault whenever the
demodulator sees the receive Eb/No fall below the pre-determined value.
•
Typical for either, when you select Masked , the modem generates no alarms.