Loop Board; Structure Of Board - Samsung SMG-400 User Manual

LOOP Board

The LOOP (Loop Start Trunk) board is an option board providing the local extension trunk
interface. It provides 4 trunk ports and each port is connected to SLC port of a Private Branch
eXchange (PBX), or the Key Telephone System (KTS).
The features and functions of the LOOP board are as follows.
It provides the signal detection function.
Impedance matching circuits are built in.
It reads the status such as the HOS and Ring Detection, Tone Detection, and Polarity
Reverse Signal etc.
It converts the analog signal into a digital signal with the PCM method to send them to the
control module. It also converts the digital signal with the PCM method into an analog
signal.
It protects the system from lightening or high voltages, AC voltage crossing etc.

Structure of Board

2-5