17
Echo 2 Mbps Multiplexer
TECHNICAL: 0118 931 2233
Each entry on a page represents a summary of link performance over 15 minutes of operation.
The
Current
entry, is updated every 10 seconds with any errors identified in the preceding
10 seconds.
To view additional entries not shown (if any) on the current screen page, move the cursor to
the
'Period end'
field, and use the
Left and Right arrow keys
. This will scroll the statistics
information up or down by one page respectively.
For diagnostics purposes it is possible to
Clear
the
Current
line (ie start a fresh line), by
moving the cursor to the
'Period end'
field, then typing <CTRL> and R. This is useful if the
operator wishes to check that a condition which may have been causing errors has been
removed.
On the screen display, the following abbreviations are used:
BVC
=
Bipolar Violation Count errors
BER
=
Approximate Bit Error Rate (based on BVC), which may be used
to trigger an alarm. Note that BER is only calculated when the
unit is in SYNC with the remote unit.
CRC
=
Cyclic Redundancy Check errors (in CRC4 mode only, otherwise
shown as '----')
FEBE
=
Far End Block Errors (in CRC4 mode only otherwise shown as '--
--')
FAS
=
Frame Alignment Signal losses
SYNC
=
Synchronisation losses (reported each time sync goes from
'present' to 'lost')
These statistics provide a very useful summary of link performance over the last 24 Hour
period.
Note that, unlike the event log, the statistics are
not
retained in the event of a power failure.
Viewing the Event Log
An event log is maintained which stores (in non-volatile memory) crucial events, such as
power up, alarms, and configuration change, and carrier loss times.
It is also possible to enable channel related events, (such as loss of external channel clock) to
be logged. These are enabled on the
System Alarms
page (see later).
