ADTRAN 12804108L1A, Системное руководство

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Section 6 Troubleshooting Guide TRACER 4108/4208 System Manual
58 © 2003 ADTRAN, Inc. 612804208L1-1B
Blue Alarm
A remote alarm (alarm indication signal or AIS) is generated by the attached equipment. The root
cause must be determined at the attached equipment. A typical cause of a blue alarm is a lack of input
to a CSU.
Recommended Actions:
1.Verify the input to any attached data equipment.
BPV
Bipolar violations (BPVs) indicate an improper configuration or faulty wiring.
Recommended Actions:
1.Verify the TRACER 4108/4208 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 4108/4208 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 will correspond to a
maximum level on the Rx Power “fuel gauge” on the TRACER 4108/4208 terminal display or maximum
voltage at the RSSI front panel test jack. 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, represents the voltage (relative to the
GND
test point) of a
relative signal level of receive strength from the far end. 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 4108/4208
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 4108/4208 microwave link. A
thorough path study can be used to estimate signal power budgets, fade margins at each receiver,