The T1HD4-XCVR card supports extensive loopback diagnostics, including command-initiated loopbacks from the CLI when provisioned for service, inband loopbacks, Facility Data Link (FDL) loopbacks, and Loopback status of the entire HDSL4 span
Faceplate LED Indicators
The T1AX has three LED indicators on the faceplate. The green ACTV LED indicates the plug-in card is communicating with a counter part T1AX in another Tellabs 1000 terminal. The ACTV LED blinks rapidly (120 flashes per minute) during self-test and provisioning, and slowly (60 flash es per minute) during a loopback test. The red FAIL LED indicates a plug-in card failure or problem communicating with the CPU. The red FAIL LED blinks when there is illegal signaling. The red LOC LED indicates a problem receiving incoming data (LOS or high BER). The green AIS LED is reserved for future use.
The second-generation T1HD2-XCVR card versions (0120-0151, 0120-0152) have the following additional features, such as up to 23 kft repeatered T1 transmission on #24 AWG copper facilities, up to 17 kft repeatered T1 transmission on #26 AWG copper facilities, interoperable with the T1X-XCVR card when an H2TU-C or H2TU-R is
used and compatible with other standards-based HDSL2 products.