User Manual

Troubleshooting
68P09255A57-2
Aug 2002
SC4812ET Optimization/ATP Manual Software Release R16.1.x.x
PRELIMINARY
6-16
All RX and TX paths fail
If every receive or transmit path fails, the problem most likely lies with
the rf converter board or the transceiver board. Refer to Table 6-27 for
fault isolation procedures.
Table 6-27: RFDS Fault Isolation - All RX and TX paths fail
Step Action
1 Visually check the master RF converter board (both board and backplane) for damage.
2 Replace the RF converter board with a known good RF converter board.
3 Visually check RXCVR TSU (both board and backplane) for damage.
4 Replace the TSU with a known good TSU.
All tests fail on a single antenna
If all path failures are on one antenna port, forward and/or reflected,
follow the procedures in Table 6-28 checks.
Table 6-28: RFDS Fault Isolation - All tests fail on single antenna path
Step Action
1 Visually inspect the site interface cabinet internal cabling to the suspect directional coupler antenna
port.
2 Verify the forward and reflected ports connect to the correct RFDS antenna select unit positions on the
RFDS backplane. Refer to the installation manual for details.
3 Visually check ASU connectors (both board and backplane) for damage.
4 Replace the ASU with a known good ASU.
5 Replace the RF cables between the affected directional coupler and RFDS.
NOTE
Externally route the cable to bypass suspect segment.
Module Status Indicators
Each of the non-passive plug-in modules has a bi-color (green & red)
LED status indicator located on the module front panel. The indicator is
labeled PWR/ALM. If both colors are turned on, the indicator is yellow.
Each plug-in module, except for the fan module, has its own alarm
(fault) detection circuitry that controls the state of the PWR/ALM LED.
The fan TACH signal of each fan module is monitored by the AMR.
Based on the status of this signal the AMR controls the state of the
PWR/ALM LED on the fan module.
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