2 faults/alarms:tx interface – Comtech EF Data SDM-2020 User Manual
Page 62

SDM-2020 Satellite Modulator
Revision 7
Front Panel Operation
MN/SDM2020M.IOM
5-20
5.6.5.2
FAULTS/ALARMS:TX INTERFACE
TX INTERFACE
------- -
Selections available include the following:
Fault/Alarm
Possible Problem and Action
FRAME SYNC
Indicates that the modulator cannot synchronize to the data in the selected
framing mode.
DATA STABLE/ASI
Note: ASI is an alarm,
not a switching fault.
Data or ASI.
When data fault is selected in the Interface Configuration menu, the fault indicates
a data stable condition. This indicates the data is all 1s or 0s (i.e., data is not
transitioning).
When ASI is selected, the alarm indicates the data is all 1s from customer data
input to the modem. When None is selected in the Configuration Interface menu,
the TX Data/ASI Fault/Alarm is not activated.
CLOCK PLL
Transmitter phase-locked loop fault. Indicates the transmitter Phase-Locked Loop
(PLL) is not locked.
CLOCK ACTIVITY
Activity detector alarm of the selected interface TX clock. The interface will fall
back to the internal clock when this alarm is active.
Note: Refer to the Configuration Interface menu, TX CLK ACTIVITY. This menu
permits selection of a fault or an alarm indication for clock activity.
FIFO
This fault indicates a data under-run/over-run condition.
INTERFACE MODULE
Interface module fault. Indicates a problem in programming the interface. This
could indicate a problem in the M&C, or in the interface between the interface
section and M&C. Return the modulator for repair.
DATA FORMAT
This fault indicates a fault with the formatted data.
VIDEO FRAME SYNC
Video Frame SYNC fault. This fault indicates a loss of synchronization to
incoming video data.
1
Use the [
←] [→] arrows to make a selection.
2
Press