Adtran TRC6420L2X Manual Do Utilizador

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TRACER 6000 Series Integrated System Manual
Section 8  Troubleshooting Guide
612806420L1-1E
Copyright © 2005 ADTRAN, Inc.
131
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.