Paradise Datacom P300-VSAT Installation & Operating Handbook page 212

Text on Display
Rx Warn: MF Back' alm Rx'd at ins' mux
Rx Warn: X.50 Back' alm from satellite
Rx Warn: RF sig too low, now <-71dbm>
Rx Warn: RF Sig too high, now <-19dBm>
Rx Warn: Eb/No below user threshold
Rx Warn: Rx BER below user threshold
Rx Warn: Buffer slips too frequent (YES)
Rx Warn: Ins' bearer BER>user threshold
P300H
Description / Cause / Notes
This fault will only be displayed if the modem if fitted with an interface which provides four ports for
separate input and output of separate Tx/Drop and Rx/Insert PCM bearers. It indicates a
Multiframe Backward Alarm is detected at the Rx bearer Input, this indicates that equipment
downstream of the RECEIVE path has failed to find Multiframe sync and is returning an alarm. The
Modem only detects this alarm when the Rx baseband is set to use the Insert mux in a G.732
mode and CAS signalling has been selected. On the Rx path, if the Insert Mux bearer is set to
Generate, then check the Rx path is also utilising CAS, otherwise it will generate a bearer without
a TS16 Multiframe.
This indicates the distant end equipment has an X.50 fault and is returning an X.50 backward
alarm. See the description for the message "Rx Fault: X.50 de-stuff sync lost" for a further
description.
The Receive RF signal level is below the range specified for this equipment. Increase the level to
ensure specified performance is met.
The Receive RF signal level is above the range specified for this equipment. Decrease the level to
ensure specified performance is met.
The Receive Eb/No (derived from the Carrier to noise ratio) is worse than the user threshold set for
a deferred alarm (Change, User-Opt, Thresholds, Eb/No). This may be used as an advance
warning of service degradation.
The final Bit Error Rate is worse than the user threshold set for a deferred alarm (Change, User-
Opt, Thresholds, User BER). This may be used as an advance warning of service degradation.
The source for the BER measurement is user defined (Change, User-Opt, Operation, Satellite,
BER est'). Normally this should be set to "Auto", however it may be user set to other BER sources
if required. It is possible to manually set the source to the inner FEC (Turbo/Vit/Seq), even when
the outer FEC (RS) is active, thereby not including the effects of the RS error correction in the
displayed user BER. Check this remains set to "Auto" unless there is good reason.
The minimum period between buffer slips is less than the user threshold set for a deferred alarm
(Change, User-Opt, Thresholds, Buffer Slip). This is used as an advance warning that the clock
accuracy is less than expected causing the buffer to slip more frequently in turn causing data
errors. The alarm may be muted by pressing YES. Check the system clocking to see if a clock has
degraded. If the clocks are correct but the buffer is slipping too frequently increasing the buffer size
will increase the period between buffer slips (but at the cost of increased delay).
This fault will only be displayed if the modem if fitted with an interface which provides four ports for
separate input and output of separate Tx/Drop and Rx/Insert PCM bearers. The Bit Error Rate at
the Rx bearer input (measured on the PCM Frame Alignment Words) is worse than the user set
threshold for a deferred alarm (Change, User-Opt, Thresholds, User BER). See note 3
P300 Series Installation and Operating Handbook
Relays To Terr To Sat Other
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