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Chapter 3: Installation
3. Installation
Before you begin, make sure all equipment, including the converters, are not
powered on.
1. Set the 4-position DIP switch as appropriate for local control signal enable and
cable distance.
2. Set the slide switch for either DCE to connect to a PC or DTE to connect to a
modem.
3. Connect the two short-haul modems with twisted-pair cable, making sure to
connect TX+ and TX- on the local unit to RX+ and RX- respectively on the
remote unit, and vice versa. You can use either the RJ-11 connector or the
4-wire terminal block.
4. Once the modems are connected together, connect DB9 cables to equipment
and power up the converters.
5. Next, power up your equipment. For testing purposes, a loopback function has
been incorporated into the short-haul modem. Placing the local unit in
loopback enables the local unit to be tested without the line, and enables the
remote unit to test the line. Placing the remote unit in loopback allows the local
unit to test the line. Keep in mind that the unit in loopback sees a cable of zero
length, while the other unit sees twice the cable length. This may affect the DIP
switch settings and the baud rate at which the test will be successful.
Table 3-1. Four-position
screw terminal connector.
Position
Function
1
TX+
2
TX-
3
RX+
4
RX-
