Tait TB9100, Installation And Operation Manual

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16 Description TB9100 Installation and Operation Manual
© Tait Electronics Limited May 2006
The network board acts as the link between the digital circuitry and the
TaitNet digital network, and gives the base station an identity as a network
element. It also provides the physical connections for the digital, analog and
RS-232 serial interfaces.
For more detailed information, see “Technical Description” on page 91 .
12V PA Base Station System
The TB9100 platform also supports the operation of a 12 V PA base station.
Figure 1.4 shows the main communication paths in a 12V PA base station
system. The 12 V PA base station system does not require a PMU, as the DC
input is connected directly to the 12 V PA. An internal boost regulator board
converts the 12V nominal DC input to a 28VDC output to power the PA
circuit boards. The boost regulator board also provides a 12VDC output to
power the reciter.
12V PA base stations use a different subrack interconnect board from base
stations with a PMU, which provides the I
2
C current source normally
provided by the PMU.
Note
The 12V PA base station subrack interconnect board has a set of
switches which must be set according to the base station configu-
ration. Refer to
“Replacing the Subrack Interconnect Board” on
page 86 for details of the switch settings.
Because there is no PMU, it is recommended that the “No PMU detected”
alarm be disabled for 12 V PA base stations.