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Section 8 Troubleshooting Guide

TRACER 6000 Series Split System Manual

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612806320L1-1B

STEP-BY-STEP TROUBLESHOOTING

The logical troubleshooting flow presented in this section can be used to set up your TRACER system or to
diagnose a previously installed system. Please contact Technical Support at any stage during installation
and/or troubleshooting if you require assistance.

INSTALLING/TROUBLESHOOTING THE TRACER HARDWARE

1. Perform a detailed path profile and link budget for each TRACER 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 hardware on a workbench. (This includes connecting the IDU and ODU

systems.) 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

PLAN A

and

PLAN B

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

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

4. Connect the IDU and ODU using the IF feedline cable. Secure one end of the RF cable to the

ANTENNA

N-type connector on the bottom of the ODU. 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 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

RF DOWN

LED on the front panel of each

TRACER unit. If the

RF DOWN

LED is illuminated (red), the corresponding TRACER is not

receiving a suitable RF signal from the other TRACER unit. In this case, the receiving TRACER is
either receiving a very weak signal or no signal at all. If the

RF DOWN

LED is not illuminated,

then the TRACER units are receiving a suitable RF signal. Suitable RF power levels for low error
rate communication range from -30 dBm to -85 dBm measured at the N-type connector input on
the TRACER unit.