Installation Guide

Table Of Contents
TETRA MBS UNIT. INSTALLATION GUIDE
F067646PT_2801
Page 61 of 62
en
8. INCIDENTS
The MBS Unit must be repaired by authorized technical personnel only. There will not
be performed any repair of the MBS Unit and it will have to be sent to factory except
for the change of the pressure equalizer or the overvoltage protections.
8.1 INTERFERENCE AT MBS UNIT
This alarm is monitored in the NMS management and configuration module. See the infrastructure
Event List in the NMS Client Help contents.
Any interference in the MBS Unit is activated when there are a large number of consecutive
reception faults in the MBS Unit. A reception fault is considered when a level higher than the threshold for
reception of the carrier, but is not recognized as valid TETRA signal. Depending on the signal level,
interference is considered low or high. So, if the level of signal is above the threshold for reception and below
the threshold set to high interference and is not recognized as a valid sign, it will be a low interference alarm.
If the signal level is above the threshold set to high interference and is not recognized as a valid signal, the
low level alarm would disappear (if it happened) and high interference would produce.
These alarms are turned off when the interference source disappears or with any right TETRA
reception for low interference case, and with more than one consecutive right reception for high-level
interference.