Troubleshooting - GE MDS SD Series Technical Manual

7.0 TROUBLESHOOTING

Successful troubleshooting of the radio system requires a logical approach. It is best to begin
troubleshooting at the Master unit, as the rest of the system depends on the Master for polling
commands. If the Master unit has problems, the overall operation of the network will be affected.
It is good practice to start by checking the simple things. For proper operation, all radios in the
network must meet these basic requirements:
• Adequate and stable primary power
• Secure cable connections (power, data and Antenna)
• An efficient and properly aligned antenna system and a received signal strength of at
least –90 dBm. (It is possible for a system to operate with weaker signals, but reliability
may suffer.)
• The correct interface between the transceiver and the connected data equipment (correct
cable wiring, proper data format, timing, etc.)
• Proper programming of the transceiver's operating parameters.
Table 14 provides suggestions for resolving system difficulties that may occur in the radio sys-
tem. If problems persist, contact the factory for further assistance. Refer to the inside back cover
of this guide for contact information.
Difficulty
Unit is
inoperative.
Interference or
signal overload is
suspected.
No link with Master,
or poor overall
performance.
No communication
to user interface
(Ethernet system).
MDS 05-4864A01, Rev. I
Table 14. Troubleshooting Guide
Recommended System Checks
a. Check for the proper supply voltage at the power connector.
b. The transceiver's internal fuse may have opened. Factory
repair normally required.
a. Use the Spectrum Analyzer/Graph function to check for
interference near the radio channel.
b. Try re-orienting the station antenna to limit interference to and
from other stations.
c. For excessively strong signals, set RX Signal Attenuation to
ON (Configuration>>Radio>>Advanced Settings). Note:
Also affects the strength of desired, on-channel signals.
a. Check for secure interface connections at the radio and the
connected device.
b. Check the antenna, feed line and connectors. Reflected power
should be less than 10% of the forward power reading
(SWR ≈ 2:1 or lower).
c. If the Remote radio links, but performance is poor, check the
received signal strength using the RSSI feature on the Radio
Performance screen. If RSSI is low, it may indicate antenna
problems, or misalignment of directional antenna headings.
d. Verify proper programming of system parameters: mode, data
interface baud rate, RF output power, etc.
e. Check for alarms using the Statistics/Events screen.
a. Verify correct IP address is set.
b. Ensure PC is set to same subnet as radio.
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