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CHAPTER 4: Installation
The DCE/DTE strap is located on the top side of the Line Driver PC board (see
Figure 4-7). The arrows on the top of the strap indicate the configuration of the
X.21 port (for example, if the DCE arrows are pointing toward the DB15
connector, the X.21 port is wired as a DCE). Change the DCE/DTE orientation by
pulling the strap out of its socket, rotating it 180º, then plugging the strap back
into the socket. You will see that the DCE/DTE arrows now point in the opposite
directions, showing the new configuration of the X.21 port. To close the case, fit
the two halves together snugly and snap them back in place.
Figure 4-7. Setting the DCE/DTE strap.
4.4 Connecting Power
The Line Driver uses a 5-VDC, 2-A 100- to 240-VAC universal input power supply
(center pin is +5V). The power supply has a male IEC 320 power entry connector.
This power supply connects to the Line Driver via a barrel jack on the rear panel.
The Line Driver powers up as soon as it is plugged into an AC outlet—there is no
power switch. The universal AC supply is equipped with a male IEC 320 connector.
DB15 (X.21)
connector
In this example, the DCE/DTE strap is configured
for DTE because the “DTE” label on the strap is
pointed toward the DB15 connector.
