User Manual

7 Troubleshooting
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Any of these problems may lead to poor or no radio communi-
cation. Check the antenna cables for damages. If there are no
damages, check the synchronization connection. If the problem
persists, the WIMAN may need to be replaced.
7.1.2 Troubleshooting with Radio Tower Installations
If the WIMAN radio modem can not be accessed over the
RS-232-interface, the problem may be caused by:
-
A non-corresponding Baud rate of the terminal program and
the WIMAN (usually the Baud rate is adjusted to 9600
Baud)
-
Incorrectly attached cables
-
Faulty Hybrid-2 or Hybrid-3-cables. Exchange the Hybrid-
2-cable first and then the Hybrid-3-cable (if necessary).
-
Faulty contacts inside the data cable plug. Check the con-
figuration and transmission with an extra 25pin data ca-
ble.
In case the ACCESS can get no RF-synchronization signal
(indicated by the Status-LED at the front side of the unit) or
if the synchronization signal reception is periodically inter-
rupted, the problem may be caused by:
-
Incorrect configuration of the ACCESS or STAR. Check
whether all parameters are correct.
-
The operating voltage at the star radio modem is too low. If
the operating voltage at the WIMAN radio modem drops
below the given threshold value, a restart is performed
automatically. It is advisable to constantly apply a volt-
age at the radio modem by at least 12V.
-
Defective or unattached antenna cable,
-
A Faulty Hybrid-2 or Hybrid-3-cable. Replace the Hybrid-
2-cable first and then the Hybrid-3-cable (if necessary).
-
Defective RF filters.
-
Defective WIMAN STAR or ACCESS.
-
Faulty contacts inside the data cable plug. Check for perfect
configuration and transmission with an additional 25pin
data cable.
-
Defective synchronization cable (short-circuit in the plug)
of and to the testing device.
-
Defective T-connector (short-circuit)