Comtech EF Data CDM-625A, Installation And Operation Manual

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CDM-625A Advanced Satellite Modem MN-CDM625A
CDM-625A ODU (Transceiver, BUC, LNB) Operation Revision 4
10–7
10.3.3.1.2.1 CONFIG: Mask

BUC
BUC alarm = Active (Active,Mask)
Attach to Tx alarm = No (Yes,No)(

)
When using L-Band, a Block Up Converter (BUC) may be included in the system. A ‘smart’ BUC
may be monitored and/or controlled via the modem via FSK (
F
requency-
S
hift
K
eying control).
For a modem in a 1:1 redundancy setup, the fault indications must be customized for
the physical setup:
1) Two modems, two LNBs in parallel – If a fault occurs on the active
modem/BUC pair and switchover is desired, the BUC mask should be configured
as Attach to Tx alarm = Yes.
2) The more common redundancy setup is Two modems in parallel, one BUC – If a
fault occurs on the active modem, switchover is desired. But, if a fault occurs on
the BUC yet a switchover of modems does not fix the problem, then switchover
should not occur and the BUC mask should be configured as Attach to Tx alarm
= No .
If the system has no redundancy and was attached to an external audio alarm,
Attach to Tx alarm = Yes would indicate that a BUC fault has occurred, as the
fault would be included in the FORM C alarms.
First, use the
▲▼
arrow keys to select BUC Alarm or Attach to Tx alarm . Then:
• For BUC Alarm , use the
▲▼
arrow keys to select Active or Masked .
•
For Attach to Tx alarm , use the
▲▼
arrow keys to select Yes or No .
Press ENTER when done.