Troubleshooting guide

Section 7, User Interface Guide - DLP-741, Provision STS-1 Network
61186003L1-1D 7-161
• From the Network Provisioning menu, select NETWORK TIMING.
• Input a value to set the desired STS-1 timing, and press ENTER. The choices are Loop,
Free-Run, and External.
- Loop timing configures the unit to recover clocking from the STS-1 receive signal.
- Free-Run timing mode is derived from a ±20 ppm internal reference.
- External timing mode configures the unit to derive clocking from the clock module.
7. From the Network Provisioning menu, select VT MODE and press ENTER.
The STS-1 can frame the 7 VT groups as either VT1.5 or VT2. The settings are as follows:
• When set for VT1.5 (T1), all VT groups are set for VT1.5[TU=11] at 1.728 Mbps and the
ports are set for T1 at 1.544 Mbps.
• When set for VT2 (E1), all the VT groups are set for VT2[TU=12] at 2.304 Mbps and the
ports are set for E1 at 2.048 Mbps.
• When set for VT2, the last 7 VTs (VT 22-28) and the last 7 DSX ports (DSX 22-28) become
unavailable.
8. From the Network Provisioning menu, select the J1 PATH TRACE OPTION, and press ENTER.
This trace message is transmitted/received in the J1 path overhead byte. This byte is
used to repetitively transmit a 64 byte (last two bytes are a fixed CR/LF) string so the
receiving terminal in a path can verify its continued connection to the intended
transmitter.
9. Press ESC as required to return to the MX2820 Main Menu.
FOLLOW-UP PROCEDURES
Once this procedure is complete, return to the procedure which called out this DLP and
continue with the tasks indicated.