Adtran TRC4202L1 Manual Do Utilizador

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TRACER 4102/4202 System Manual
Section 6  Troubleshooting Guide
612804202L1-1A
© 2004 ADTRAN, Inc.
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2. Setup all of the TRACER hardware on a workbench. ADTRAN recommends that the actual cables 
used in the permanent installation be used in the workbench setup. A rigorous workbench 
“simulation” of the link will help alleviate and avoid time-consuming errors.
3. Examine the 
PLAN A
 and 
PLAN B
 LEDs on the front panel of each unit. These LEDs indicate the 
frequency plan for each TRACER 4102/4202 unit. The frequency plan (Plan A, Plan B) LED 
should be the opposite on the TRACER 4102/4202 units. 
4. Verify that both ends of the link are configured for the same RF Bandplan (1, 2, or 3). See 
5. Verify that both ends of the link are configured for the same number of active T1 ports. See 
6. Attach the RF coaxial cables to be used in the permanent installation to the N-type connectors on 
the back of the TRACER 4102/4202 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 
will be the RF power available at the input of the antenna. The TRACER 4102/4202 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 any combination of either unsuitable RF, or faulty, or unreasonably long coaxial cable.
7. Resolve all RF coaxial cabling errors before proceeding.
8. 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 be accounted for.
9. After setting up the RF pieces, examine the 
RF DOWN
 LED on the front panel of each
TRACER 4102/4202 unit. If the 
RF DOWN
 LED is illuminated (red), the corresponding
TRACER 4102/4202 is not receiving a suitable RF signal from the other TRACER 4102/4202 unit. 
In this case, the receiving TRACER 4102/4202 is either receiving a very weak signal, or no signal 
at all. If the 
RF DOWN
 LED is not illuminated, then the TRACER 4102/4202 units are receiving a 
suitable RF signal. Suitable RF power levels for low error rate communication will range from
-30 dBm to -100 dBm (TRACER 4102) or -30 dBm to -96 dBm (TRACER 4202) measured at the 
N-type connector input on the TRACER 4102/4202 unit.
10. Resolve any signal level issues before proceeding.
11. Examine the 
RF LOW
 LED on the front panel of each TRACER 4102/4202. If this LED is 
illuminated, then the TRACER 4102/4202 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 4102/4202 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.