Motorola DIMETRA MTS 2, Installation, Configuration And Basic Service Manual

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XHUB Chapter 1: MTS Overview
XHUB
The eXpansion HUB (XHUB) is a non-intelligent switching and interface module, which plugs into
the Site Controller slot of an MTS 4 Expansion Cabinet. It is connected through the Expansion
Cab output of the Site Controller to the Prime Cab connector of the XHUB.
Base Radio (BR)
The Base Radio (BR) module contains the following sub-components:
•
Transceiver
•
Power Ampli
fi
er (PA)
Transceiver
The transceiver provides the BR's transmission, receiving, signal processing, and modulation functions. To do
this, the transceiver incorporates a Base Radio Controller (BRC), Receiver (RCV), and Exciter (EXC).
The BRC serves as the main controller of the Base Radio. The BRC provides signal processing
and operational control for the other Base Radio modules.
Power Amplifier
The Power Ampli
fi
er (PA), in conjunction with the Exciter, provides the transmitter functions
for the Base Radio. The PA accepts the low-level modulated RF signal from the exciter and
ampli
fi
es the signal for transmission through the RF output connector.
Power Supply Unit
Depending on the con
fi
guration, the MTS is equipped with one or two Power Supply Units (PSUs).
The PSU permits operation of the MTS in any of the following con
fi
gurations:
•
DC power supply
•
AC power supply
•
AC power supply with a DC backup battery
Backup Battery
The PSU handles the automatic switchover to a backup battery in the event of an AC power supply
failure. The MTS charges the backup battery during normal AC operation. A temperature sensor
monitors the backup battery’s temperature to ensure optimum charging.
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6802800U74-N September 2009