Nortel DualMode 800, Maintenance Manual

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Nortel Networks Confidential Transmit Receive Unit (TRU) 1-25
Wireless Solutions DualMode 800 Enclosure Maintenance Manual MTX08
Note 1: Loss-of-service conditions which are not detected by the radio,
such as excessive SWERRs, do not cause the yellow LED to turn on
directly. However, if the ICP chooses to close the signalling connection to
the radio, the yellow LED will be activated indirectly and further
6 In-service
—DCCH or
2T+C On Off Off On Off On During normal operation, the TX LED
turns on whenever the radio’s
transmitter is active.
Radio remains in this state until one of
the followings happens:
—external failure detected, radio goes
to state 7
—internal hardware failure detected,
radio goes to state 8
—radio taken out of service by the MTX
(SYBSY) or by an operator (MANB),
radio goes to state 2
In-service
—TTC
(transmitter
active) On Off Off Off Off On
In-service
—TTC
(transmitter
inactive) On Off Off Off Off Off
7 LOS On On
(Note
1) Off Last
state Last
state Last
state
(Note
2) This state indicates that a failure
outside the radio has occurred. Typical
loss of service conditions include: PA
fault, Link Access Protocol-D (LAPD)
link disconnection, or a loss of
connection to the Digital Signal
Processing Module (DSPM). The MTX
will take the radio out of service (state
2) once the LOS condition is reported
with the exception of loss connection to
DSPM. The radio is reported as in-
service trouble state. Service is
restored when the connection to the
DSPM is re-established.
8 Fault Off Off On
(Note
3) Off Off Off
This state indicates that an internal
hardware fault is detected. The MTX
will take the radio out of service (state
2) once the fault is reported. The fault is
reported to the MTX as an MTX105 log.
Refer to the
DualMode Radio Unit
Troubleshooting Guide , 411-2131-166,
for more information.
- End -
Table 1-1
Transitions in the TRU3 LED state (continued)
State Status LED Description/Action
ON LOS FAIL CCH LCR TX