Paradise Datacom P300-VSAT Installation & Operating Handbook page 209

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Rx Fault: <line> off, <DTE/DCE> not ready
Rx Fault: <line> off, DCE not accp't Rx data
Rx Fault: No insert bearer, generating
Rx Fault: Insert bearer AIS, generating
Rx Fault: Ins mux bearer frame sync lost
Rx Fault: Ins mux bearer MF sync lost
Rx Fault: Ins mux bearer CRC sync lost
P300H
Description / Cause / Notes
<line> depends on the interface in use (eg RS422 DCE="TR", V.35="DTR"). This is a DC control
line which is used to indicate the terrestrial equipment is functioning properly. The <line> switching
off may be user set to cause this fault or be ignored (Change, Terr-Int, Control Lines). See note 5.
<line> depends on the interface in use and is only available if the modem is fitted with a DTE
interface card (eg RS422 DTE="CS", V.35="CTS"). This is a handshake line which is raised in
response to our RS/RTS line (if the modem interface is a DTE) which in turn indicates the output
data is valid (ie demod locked and FEC/deframing OK). It's status can be used to determine if the
terrestrial device is accepting the modems output data. The <line> switching off may be user set to
cause this fault or be ignored (Change, Terr-Int, Control Lines). See note 5
If the Rx Baseband is set to Insert Mux, with the bearer Looped through from the Drop Mux
(dialogue under Change, Rx, Baseband, Insert) then if the Tx input signal fails (no bearer or AIS)
then this looped bearer onto which the Rx traffic is to be inserted is not available and the Rx data
would therefore be lost as a result of a Tx fault. In such a circumstance the modem temporarily
generates a PCM bearer onto which the Rx data can be inserted to preserve the Rx traffic. See
notes 6 & 9
See above, see notes 6 & 9.
The modem only detects frame sync when the Insert Mux is active. Check the bearer type is
specified correctly (Change, Rx, Baseband, Insert). This normally only occurs if either there are
significant errors on the terrestrial link, or if it is supplied with AIS and the modem is set to ignore
AIS. Check that the AIS detector is not disabled with Change, User-Opt, Operation, Actions, AIS.
ALSO there is an option to make the modem re-seek frame sync if CRC sync is lost (Change,
User-Opt, Operation, Terrestrial, PCM Bearer CRC, CRC/Frame Acq'). Check the modem is not
set to expect a CRC and forcing frame re-acquisition if CRC is lost, but there is no CRC on the
PCM signal. See notes 6 & 9
The modem only seeks TS16 Multiframe sync when the Rx baseband is set to use the Insert mux
in a G.732 mode and CAS signalling has been selected. Check that a CAS multiframe is present
on the PCM signal applied to the modem (ie terrestrial TS16 contains the 16 frame Multiframe
sequence). See note 9.
The modem only seeks Cyclic Redundancy Code (CRC) sync when the Rx baseband is set to use
the Insert mux in G.732 mode and when set by the user to process CRC's (Change, User-Opt,
Operation, Terrestrial, PCM Bearer CRC, Process). If CRC sync is permanently lost, check if a
CRC is present on the PCM signal.
P300 Series Installation and Operating Handbook
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