Section 6 Troubleshooting Guide
TRACER 4102/4202 System Manual
58
© 2004 ADTRAN, Inc.
612804202L1-1A
BPV
Bipolar violations (BPVs) indicate an improper configuration or faulty wiring.
Recommended Actions:
1.
Verify the TRACER 4102/4202 unit and the attached equipment are configured for the same line
coding (
B8ZS
or
AMI
).
2.
Verify the cable connections for the T1 interface are solid.
3.
RF ERRORS
RF errors can range from a nonviable microwave path to loose RF connectors.
Nonviable path conditions could be caused by physical obstructions such as buildings, moutainous terrain,
trees, etc., as well as other physical limitations such as excessive path distances and in-band RF
interference. These types of errors are remedied by performing a detailed line-of-site microwave path
study to determine whether a microwave link is feasible for the terrain and environment under
consideration.
If after performing a microwave path study the system is still not operational, ensure that the antennas are
properly aligned. Note that alignment must be achieved in both elevation and azimuth for optimal link
performance. The TRACER 4102/4202 can be used to aid in antenna alignment by looking at the
R
X
P
OWER
“fuel gauge” on the System Status or System Option menu pages or by measuring the DC voltage
(relative to ground) at the RSSI front panel test jack. Optimal antenna alignment is achieved by peaking the
front panel RSSI voltage or the the Rx Power "fuel gauge" on the TRACER 4102/4202 terminal diplay.
Consult the ADTRAN TRACER Data Sheet included with the unit to verify that the actual receive signal
level agrees with the calculated receive signal.
An RSSI test point, located on the front panel, provides a DC voltage level (relative to the GND test point)
that corresponds to the amount of signal being received from the far end's transmitter. The voltage at this
test point can vary from approximately 0 to 5 Volts DC. An RSSI Calibration sheet is shipped with the
system to provide the installer a cross-reference between actual received signal level (in dBm) and RSSI
voltage. This sheet is useful for verifying link budget calculations and ensuring proper equipment
installation.
4.
STEP-BY-STEP TROUBLESHOOTING
The logical troubleshooting flow presented in this section can be used to set up your TRACER 4102/4202
system, and also to diagnose a previously installed system. Please contact ADTRAN Technical support at
any stage during installation and/or troubleshooting if you require assistance.
5.
INSTALLING/TROUBLESHOOTING THE TRACER HARDWARE
1. Perform a detailed path profile and link budget for each TRACER 4102/4202 microwave link. A
thorough path study can be used to estimate signal power budgets, fade margins at each receiver,
identity potential line-of-site obstacles, properly size antenna dishes, and determine minimum
antenna dish heights above the earth.
ADTRAN provides a wireless link planning tool on our website. This link budget tool is
constructed as an easy to use spreadsheet with dropdown menus so that the user can
quickly change any of the link parameters (antenna size, coaxial cable type and length,
frequency band, link distance, etc) and instantly see how the microwave path availability is
affected. This tool is available at
and can be used online or
downloaded for standalone use.
