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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.
y
It provides the signal detection function.
y
Impedance matching circuits are built in.
y
It reads the status such as the HOS and Ring Detection, Tone Detection, and Polarity
Reverse Signal etc.
y
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.
y
It protects the system from lightening or high voltages, AC voltage crossing etc.
Structure of Board
