1. Open the unit by gently inserting a screwdriver between the
DB-25 connector and the lip of the plastic case (see below).
You don't have to worry about breaking the plastic, but be
careful not to bend the D-sub connector.
Once the unit has been opened, you will be able to see the
terminal blocks located at the rear of the PC board.
2. Strip the outer insulation from the twisted pairs about one inch
from the end.
3. Strip the insulation on each of the twisted pair wires about .25”.
4. Connect one pair of wires to XMT+ and XMT- (transmit
positive and negative) on the terminal block, making careful
note of which color is positive, and which color is negative.
5. Connect the other pair of wires to RCV+ and RCV- (receive
positive and negative) on the terminal block, again making
careful note of which color is positive and which color is
negative.
Ultimately, you will want to construct a two pair crossover
cable that connects the two short hauls as shown below:
6. If there is a shield around the telephone cable, it may be
connected to “G” on the terminal block. To avoid ground
loops, we recommend connecting the shield at the computer
end only. A ground wire is not necessary for proper operation
of the Model 1005.
7. When you finish connecting the wires to the terminal block, the
assembly should resemble the diagram below:
87
XMT + RCV+
XMT - RCV -
G G
RCV - XMT -
RCV + XMT +
To Shield (Optional)
}
One Pair
}
One Pair