Chapter 4 Tutorial
T1/E1 Local Loopback Test
4-5
TC8612 Rev 1.1 User Manual
4.6
T1/E1 Local Loopback Test
A T1/E1 Local loopback is used to test T1/E1 wiring and T1/E1 transceiver
functionality. It can be enabled by pushing both rear panel DIP switches SW1 &
SW2 to the “On” (Down) position. The diagram below shows the T1/E1 signal flow
and related loopback path.
1.
The “ALM” LED should be flashing indicating the unit is in T1/E1 Loopback
mode.
2.
The “LOS” LED should be off indicating that a valid T1/E1 signal is being
received. If the “LOS” LED is flashing it means that the TC8612 is not
receiving a valid T1/E1 or the T1/E1 cable is in question.
3.
The T1/E1 signal should be looped back to the Carrier/Service Provider or T1/
E1 tester. Please make sure a valid T1/E1 signal is being received.
4.
Upon successful completion of this test, please return dip switches
SW1(LOCLB) and SW2(RMTLB) to the “Off ”(Up) position for normal
operation of the TC8612 unit(s).
