Adtran TRC6410L2X Manual Do Utilizador

Section 8  Troubleshooting Guide

TRACER 6000 Series Integrated System Manual

 128

Copyright © 2005 ADTRAN, Inc.

612806420L1-1D

1. Perform a detailed path profile and link budget for each TRACER 64x0 microwave link. A 

thorough path study can be used to estimate signal power budgets, estimate fade margins at each 
receiver, identify potential line-of-site obstacles, properly size antenna dishes, and determine 
minimum antenna dish heights above the earth.

2. Set up all of the TRACER 64x0 hardware on a workbench. The actual cables used in the 

permanent installation should be used in the workbench setup. A rigorous workbench “simulation” 
of the link will help alleviate and avoid time-consuming errors.

3. Examine the 

 and 

 LEDs on the front panel of each unit. These LEDs indicate the 

frequency plan for each TRACER 64x0 unit. Each TRACER link must have a Plan A radio on one 
side and a Plan B radio on the other.

4. Attach the RF coaxial cables to be used in the permanent installation to the N-type connectors on 

the back of the TRACER 64x0 unit. Attach the other end of the coaxial cable(s) to an RF power 
meter or spectrum analyzer, if either is available. The power measured by the meter/analyzer is the 
RF power available at the input of the antenna. The TRACER 64x0 unit is programmed at the 
factory to output approximately 100 mW (20 dBm) of RF power. The actual power level measured 
by the meter/analyzer will be less than 100 mW due to RF losses through the coaxial cable, and is 
a function of the cable type and length being used. In any event, the power level at the output of 
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 

 LED on the front panel of each

 

TRACER 64x0 unit. If the 

 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 

 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 

 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 

 LED is 

not illuminated, then the received signal is being suitably processed by the TRACER 64x0 system. 
If you are receiving a weak signal (

 is 

), 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.