Service manual

Description: Functional Theory of Operation 1-17
Figure 1-7 Wireline Functional Block Diagram
Surge
Protection
Surge
Protection
DC
Remote
Decoder
Jumpers
RX
Audio
TX Audio
(2-Wire TX/RX)
Decoded DC
Control Signals
(to FPGA)
Impedance
Matching
Network
Impedance
Matching
Network
D/A
A/D
A/D
CODEC
FPGA
...
...
Wireline
CODEC
D/A
A/D
RX Audio
from Control Board
and J7 DB25
TX Audio
to Control Board
and J7 DB25
SPI Bus
To/From
Control Board
GPIO Signals
To/From
Control Board
and J7 DB25
Decoded DC
Control Signals
Line 2
Line 1
Select 2W/4W
Station Backplane (J4)