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
6–80
Alarm Type Description
Rx
(Receive)
Demod Lock
Indicates either the demodulator or the following FEC decoder cannot
lock to the incoming signal.
AGC Alarm Indicates if the demod signal level is out of range.
Frame Sync
Indicates that the de-framing unit (EDMAC, IBS or IDR) or Reed-
Solomon outer decoder cannot synchronize to the data being sent to it
by the demod and/or FEC decoder.
CnC Lock
Indicates that the CnC cancellation algorithm has correctly convaerged
and is successfully tracking.
Buffer Slip
Occurs when Doppler or Plesiochronous effects cause the Rx data
buffer to empty or fill completely, which results in a reset to 50%.
Rx AIS
Alarm Indication Signal (all 1’s) is monitored if present at the Rx
satellite input.
EbNo Alarm
Occurs when the monitored level drops below what was programmed
via menus: Config, Rx, EbNo Alarm point.
Buffer Clock
Indicates that the desired buffer reference is not present, causing the
buffer to fall back on Rx satellite timing to clock its output.
Net (Unit
Network)
Loss TxFrm
Loss of Tx frame occurs in Drop & Insert operation, when the incoming
T1 or E1 frame cannot be found by the modem.
BER >10E-3 This error rate monitor is enabled for IBS and IDR framing.
Loss TxMul
Loss of Tx multiframe occurs in E1-CAS D&I operation, when the
multiframe marker for CAS signaling data cannot be found.
Tx Sig AIS
An AIS condition in the signaling positions of an incoming E1-CAS
frame is monitored.
Tx Terr RM
Indicates the presence of the Tx terrestrial remote alarm on the
incoming T1 or E1 frame.
IBS Rx Rem
Indicates the presence of the IBS satellite remote alarm (backward
alarm) on the incoming IBS frame from the transmit side of the link.
IDR Rx BW1-4
Multi-destination backward alarms are the corresponding satellite
alarms used by the IDR frame structure.
IDR Tx BW1-4
Backward alarms 1-4 indicate that the hardware inputs available on the
back panel of the modem have triggered, resulting in the generation, by
the modem’s IDR framer, of a corresponding Tx backward alarm.
BUC
Chapter 10. CDM-625A ODU (TRANSCEIVER, BUC, LNC) OPERATIONS
LNB