User Manual

SCCP Backplane Troubleshooting – continued
08/15/2000
6-15
SC 4812ETL BTS Optimization/ATP
PRELIMINARY
GLI2 Ethernet “A” and “B” Connections
These BNC connectors are located on the SCCP backplane and routed to
the GLI2 board. This interface provides all the control and data
communications between the master GLI2 and the other GLI2, between
gateways, and for the LMF on the LAN.
BBX2 Connector
Each BBX2 connector consists of a Harting 2SU/1SU digital connector
and two 6–conductor coaxial connectors. These connectors provide DC,
digital, and RF inputs/outputs for the BBX2s in the SCCP backplane.
CIO Connectors
S RX RF antenna path signal inputs are routed through RX Tri–Filters
(on the I/O plate), and via coaxial cables to the two MPC modules –
the six “A” (main) signals go to one MPC; the six “B” (diversity) to
the other. The MPC outputs the low–noise–amplified signals via the
SCCP backplane to the CIO where the signals are split and sent to the
appropriate BBX2.
S A digital bus then routes the baseband signal through the BBX2, to
the backplane, then on to the MCC24 slots.
S Digital TX antenna path signals originate at the MCC24s. Each
output is routed from the MCC24 slot via the backplane appropriate
BBX2.
S TX RF path signal originates from the BBX2, through the backplane
to the CIO, through the CIO, and via multi-conductor coaxial cabling
to the LPAs in the LPA shelf.
SCCP Backplane
Troubleshooting Procedure
The following table provides a standard procedure for troubleshooting
problems that appear to be related to a defective SCCP backplane. The
table is broken down into possible problems and steps which should be
taken in an attempt to find the root cause.
It is important to note that all steps be followed before
replacing ANY SCCP backplane.
IMPORTANT
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