Comtech EF Data SMS-758 - Manual (Page 113)

MN/SMS758 Rev. 3 5–1
Chapter 5.
MAINTENANCE
5.1 Fault Descriptions
The FAULT menu, [NEXT], and [PREV] keys allow the operator to determine the cause
of any switch faults indicated by a red LED.
The following sections describe the faults and their probable causes.
5.1.1 Modulator Operation Fault
A MOD fault occurs when a modulator backup operation fails. The cause of the failure
can be one of the following:
•
More failed modulators than available backups.
•
No compatible backup available.
•
All backups in use and/or faulted.
5.1.2 Demodulator Operation Fault
A DEMOD fault occurs when a demodulator backup operation fails. The cause of the
failure can be one of the following:
•
More failed demodulators than available backups.
•
No compatible backup available.
•
All backups in use.
•
All demodulators on a downlink faulted.