Tx Interface Faults; Rx Interface Faults - Comtech EF Data SDM-100A Installation And Operation Manual

SDM-100A Satellite Modem

3.2.1.3.3 TX Interface Faults

TX Clock Activity
TX Audio Clip

3.2.1.3.4 RX Interface Faults

Buffer Clk Act
Buffer Underflow
Buffer Overflow
RX Audio Clip
DEMUX Lock
Remote Off Hook
Rev. 0
Fault/Alarm
Activity detector alarm of selected interface transmit clock. Indicates the
selected TX clock is not being detected.
Check the signal of the selected TX clock source to verify the signal is
present. The interface will fall back to the internal clock when this alarm is
active.
With ADPCM option on, excessive input sensed on TX+ and TX- interface
lines.
Fault/Alarm
Activity detector alarm of the selected interface receive clock. The
interface will fall back to the satellite clock when this fault is active.
Buffer Underflow Alarm. The plesiochronous buffer has underflowed.
As buffer underflow is normally a momentary fault (there are clock
problems if this is continuously present), this is included in this section to
be consistent with the fault reporting system and be correctly registered in
the "Stored Fault" memory. The time and date of the last 10 Receive "Buf
Underflow" faults are stored in battery-backed memory as an aid to
troubleshooting. The interval between stored Overflow/Underflow events
can be used to determine relative clock accuracy.
Buffer Overflow Alarm. The plesiochronous buffer has overflowed.
Refer to the "Buffer Underflow" row above for problems and actions, as
the same comments apply.
With ADPCM option on, excessive input received by DEMUX.
Indicates loss of DEMUX lock. (ASYNC/ADPCM option.)
Indicates that the remote handset has signaled off hook.
Possible Problem and Action
Possible Problem and Action
Operation
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