ADTRAN 6000 Series system manual 612806420L1-1F Copyright 2005 ADTRAN, Inc 131

TRACER 6000 Series Integrated System Manual Section 8 Troubleshooting Guide

the coaxial cable should be a significant fraction of 100 mW. A power meter/analyzer reading that is not on the order of at least tens-of-milliwatts could be an indication of unsuitable RF cable or faulty or unreasonably long coaxial cable, or a combination of these factors.

5.Resolve all RF coaxial cabling errors before proceeding.

6.Attach the RF coaxial cables to a high-quality attenuator, if possible. If you do not have an attenuator, attach the coaxial cables to the antennas to be used in the permanent installation. If the installation antennas are not available, small, inexpensive dipole or patch antennas can be used for verification purposes. If an adjustable attenuator is being used, dial in the amount of attenuation that corresponds to the path loss value expected for the microwave link in which the TRACER hardware will be installed. The path loss value can be calculated from a knowledge of the path length, or provided by a path study. Remember to subtract both antenna gain values from the attenuator level if these values have not already been accounted for.

7.After setting up the RF pieces, examine the RF DOWN LED on the front panel of each

TRACER 64x0 unit. If the RF DOWN LED is illuminated (red), the corresponding TRACER 64x0 is not receiving a suitable RF signal from the other TRACER 64x0 unit. In this case, the receiving TRACER 64x0 is either receiving a very weak signal or no signal at all. If the RF DOWN LED is not illuminated, then the TRACER 64x0 units are receiving a suitable RF signal. Suitable RF power levels for low error rate communication range from -30 dBm to -88 dBm measured at the N-type connector input on the TRACER 64x0 unit.

8.Resolve any signal level issues before proceeding.

9.Examine the RF LOW LED on the front panel of each TRACER 64x0. If this LED is illuminated, then the TRACER 64x0 is receiving a relatively weak signal; however, if the RF DOWN LED is not illuminated, then the received signal is being suitably processed by the TRACER 64x0 system. If you are receiving a weak signal (RF LOW is ON), please verify that the weak signal is not being caused by a faulty cable, an insufficiently tightened cable, or some other installation-related problem. Also, make sure an unreasonably large attenuation value has not been selected if you are using an attenuator on a workbench setup.

Use the tables in Section 2, Microwave Path Engineering Basics, on page 15, of this manual to select the proper free-space attenuation value (in dB) based on the estimated length of the microwave path. Remember to subtract both antenna gains (local and remote) from the attenuator setting.

10.Test the installed modules by performing the following steps:

4xT1 Module

Initiate a line loopback on the local TRACER 64x0 unit and run a test pattern from the connected T1 equipment. This will verify the connection between the T1 equipment and the local TRACER 64x0 unit.

612806420L1-1F Copyright © 2005 ADTRAN, Inc. 131