TOA Electronics EX-16 - Manual (Page 7)

(c) LAU (Line Amplifier Unit)
The Line Amplifier Unit consists of a power supply circuit for stations,
transmitting and receiving circuits for voice signal, speech path switches,
BGM switches and the dial data receiving circuits.
One unit accepts up to 4 stations. A maximum of 4 LAU's can be installed.
(d) DSM (Power Supply Module)
The Power Supply Module consists of a power supply unit for the exchange
and terminals for external input and output connections. This module is
attached to the mother board with a connector and can be easily detached
from the exchange.
AC in
GND
DC in
remote
BGM in
paging out
power
supply
circuit
5V
18V
24V
GND
receiving
circuit
switch
T
switch
R
transmitting
circuit
control signal
BGM/AII
call/Link
busy
dial data in
dial
receiver
out
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