Black Box MT1100A, Руководство пользователя

Страница: 18 / 26

Chapter 4 Troubleshooting and Diagnostics
4-2 Troubleshooting
To activate the local analog loopback from the standalone unit:
1. Open the unit’s case, as described in Chapter 2 .
2. Set the JP11 jumper to LOC.
The analog loopback is activated and the TST indicator on the front panel
turns on.
To activate the local analog loopback from rack card:
•
Press the ANA pushbutton on the card’s front panel.
Make sure that the PNL SW jumper (JP5) on the card’s board is set to EN.
The TST indicator on the front panel turns on.
Deactivating Local Analog Loopback
To deactivate the local analog loopback from the DTE:
• Lower the circuit 141 pins of the DTE interface.
To deactivate the local analog loopback from the standalone unit:
• Set the JP11 jumper to DTE.
The TST indicator on the front panel turns off.
To deactivate the local analog loopback from the rack card:
• Press the ANA pushbutton again to return it to the previous position.
4.2 Troubleshooting
Table 4-1
contains troubleshooting information to help you identify and correct
problems.
Table 4-1. Troubleshooting
Trouble Symptoms Probable Cause Corrective Measures
All front panel indicators
are OFF 1. No power Check that both ends of the power cable
are properly connected.
2. Blown fuse Disconnect power cable from both ends
and replace the fuse with another fuse of
proper rating.
LOS indicator is ON 1. Receive line fuses are blown Disconnect power cable from both ends
and replace the fuses with new fuses of
proper rating.
2. Line cables are not properly
connected
Check and adjust both ends of the line
cables.
3. Unbalanced BNC connectors
are reversed
Switch the two BNC connectors.
4. The transformer is damaged Replace the unit.