Paradyne Jetstream CPX-1000 - Manual (Page 114)

4. Troubleshooting 1000-A2-GN22-00
4-14 February 2003
Loopbacks
The CPX supports near-end loopback on T-1 ports as a diagnostic
tool to test connectivity to external devices. During a loopback
procedure, the transmitted signal is returned to the sending device
to verify that there were no transmission errors.
Use these steps to perform a loopback from JetCraft or JetVision:
Step 1 Lock the card.
Step 2 Set the port to loopback status.
Step 3 Temporarily remove any existing T-1 cable from the port and
connect a loopback plug to the port.
Step 4 Observe the results of the loopback test.
Step 5 When the loopback test is complete, remove the loopback plug and
reconnect the T-1 cable removed in
Step 3 .
Step 6 Set the port to No Loopback.
Step 7 Unlock the port, returning it to normal operation.
Refer to the JetCraft User’s Guide or JetVision User’s Guide for further
details.
Note
To create a loopback plug, use a short length of T-1 cable
with a jack on one end. Connect pins 1 and 4, and pins 2
and 5. Test the connections for continuity.