Power Amplifier Circuit Description - Tait TB8100 Service Manual

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Power Amplifier Circuit Description

TB8100 Service Manual
© Tait Electronics Limited September 2006
The TB8100 power amplifier (PA) is a modular design with the circuitry
divided between separate boards. These boards are assembled onto a
heatsink in different configurations in different models.
Figure 7.1 on page 114
50W 12V PA, along with the main inputs and outputs for power, RF and
control signals. The 100W PA consists of:
a 6W board
two quadrature-combined 60W boards
a splitter board and a combiner board
a low pass filter and directional coupler board
a control board.
The configuration of the 50W PA is similar, but it uses only one 60W board
and does not require the splitter or combiner boards. The 5W PA does not
use the 60W, splitter or combiner boards.
The 12V PA is fitted with an internal boost regulator board, which converts
the 12VDC nominal supply to the 28VDC required by the PA. Apart from
this boost regulator board, the circuitry of 12V PAs is identical to the
standard 28V models. Only 5W and 50W PAs are available for operation
on 12VDC.
RF interconnect boards are also used in some configurations to connect the
boards together. The type of interconnect board used depends on the
configuration of the PA.
page 131 show the different configurations used in different models.
The locations of the main circuit blocks on the boards are shown in
Figure 7.3 on page 123
shows the configurations for a 100W 28V PA and
Figure 8.1 on page 130
and Figure 7.4 on page
Power Amplifier Circuit Description
and Figure 8.2 on
125.
113