damage the pc-board mounted components.
The DCE/DTE strap is located on the top side of the MDU9705A-
X21 pc board (See Figure 8, below). 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 DB-15 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 2 halves together snugly and snap them back
in place.
Connecting Power
The Compact mDSL Modem (all versions) are available with
Universal AC (100-240VAC), 120VAC, 230VAC or -48VDC power
options. This section describes these options.
Universal AC Power (100-240VAC)
The Compact mDSL Modem uses a 5VDC, 2A universal input
100-240VAC, power supply (center pin is +5V). The universal input
power supply has a male IEC-320 power entry connector. This power
supply connects to the Compact mDSL Modem by means of a barrel
jack on the rear panel. Many international power cords are available
for the universal power supply (Please refer to Appendix B for country-
specific power cords.
The Compact mDSL Modem powers up as soon as it is plugged
into an AC outlet--there is no power switch.
DCE/DTE Strap
DB-15 Connector
Figure 8. Setting the DCE/DTE Strap
13
Compact mDSL Modem
14
Compact mDSL Modem
120 VAC Power (US)
The 100-132 VAC adapter supplied with the U.S. version of the
Compact mDSL Modem is a wall mount type and may be plugged into
any approved 120 VAC wall jack.
230 VAC Power (International)
The 230 VAC adapter supplied with the International version of the
Compact mDSL Modem is a wall mount type and may be plugged into
any approved 230 VAC wall jack.
DC Power
The 36-60 VDC DC to DC adapter supplied with the DC version of
the Compact mDSL Modem plugs in a DC source (nominal 48VDC)
and plugs into the barrel power supply jack on the rear of the Compact
mDSL Modem. Please refer to Figure 9, below, to make the proper
connection.
Figure 9. Connecting DC Power to the 48VDC Power Supply.
WARNING!
There are no user-serviceable parts in the
power supply section of the Compact mDSL Modem. Fuse
replacement should only be performed by qualified service
personnel.
To Power
Supply Jack
-Vin
+Vin
To -48VDC
Source
