ZyXEL Communications U-336E, User Manual

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Leased Line Operation 27
4
Leased Line Operation
A leased line is a permanent telephone line connection between two
fixed points. It can be dedicated copper wires or a leased telephone
circuit from the telephone company. Four-wire leased lines use one
pair of wires to transmit data and a second pair to receive. Two-
wire leased lines transmit and receive on the same pair of wires.
Your modem supports 2 -wire leased lines only.
Connecting to a Leased Line
The U-336E default line is a dial-up type. The leased line must be
connected to the jack labeled Line. Set your modem for leased-line
operation by typing commands from the terminal. The leased-line
phone jack pin assignments are shown in Chapter 11 Connector
Pinouts.
Power Level Setting
Your modem’s leased-line mode transmission power level can be
adjusted from 0 dBm to -27 dBm in 1 dBm increments.
AT-Command Description
AT*P0
. . .
AT*P15 The default is -9dBm. The adjustable range is
from 0 to -15dBm, effective in leased-line
operation only. If bit 3 of S35 is set, this range
will change to -12 to -27dBm.
Leased Line Handshaking
In a typical dial-up connection, the originating modem dials the
number and waits for the answering modem's carrier signal. The