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Page
2
‐
6
GMA
347
Maintenance
Manual
Rev.
A
190
‐
00325
‐
02
Main
Board
Assembly
The
Main
Board
Assembly
contains
the
Power
Supplies,
a
CPU/FLASH/RAM
bus,
an
FPGA
which
provides
audio
switching
and
mode
control,
a
Class
D
switching
Audio
Amp,
and
the
Marker
Beacon
Receiver.
Audio
Board
Assembly
The
Audio
Board
Assembly
contains
all
circuitry
necessary
to
perform
the
audio
switching
and
isolation
functions
(FPGA,
comparators,
switches,
drivers,
and
amplifiers).
Front
Panel
Board
Assembly
The
Front
Panel
Board
Assembly
contains
the
panel
lighting,
button
annunciator
LEDs,
and
front
panel
button
switches.
