Chapter 2 – Activation and Installation
12
Multi-Tech Systems, Inc. MultiModem Cell User Guide
Connect the Antenna, Serial or USB Cable, Power, Optional
Power or Voice Cable
1.
Connect a suitable antenna to the ANT connector on the right side of the unit (see antenna specifications in Chapter 1).
2.
If you are connecting to a serial interface, connect a serial cable to the RS232 connector on the back of the unit and
connect the other end of the serial cable to the serial port on your PC.
If you are connecting to an USB interface, connect an USB cable to the USB connector on the back of the unit and the
other end to the USB port on your PC.
3.
Set the 4-position DIP Switch on the back of the unit to the configuration of your unit.
Switch Position
Up/On
Down/Off
Description
Position 1
Off
DTR Reset Disabled
Position 1
On
DTR Reset Enabled
Positions 2-4
Only valid for serial builds
Position 2
Off
No TXD Terminiation
Position 2
On
TXD Diff Pair Terminated
Position 3
Off
No RTS Termination
Position 3
On
RTS Diff Pair Terminated
Position 4
Off
RS232 Mode
Position 4
On
RS422 Mode
Note: Positions 2 and 3 should only be used in RS422 Mode. Enabling TXD/RTS termination may be required
to avoid errors at high bit rates or long cable lengths. Multi-Tech Systems tested the cable up to 1,000 feet , but
the maximum may be more with termination enable and lower data rates.
4.
If you are connecting a hand set to the unit for voice communication, connect an RJ11 cable from the hand set to the
VOICE connector on the back of the unit. To adjust the volume of the hand set, refer to the appropriate AT Command
Reference Guide on your product CD.
5.
Depending on the power source, connect either the power supply module with the appropriate blade or the optional DC
power cable. If you are using the power supply module, remove the protective shipping cover. Attach the appropriate
interchangeable blade piece to the power supply module.
Screw-on the power lead from the power supply module to the power connection on the modem. Now, plug the
power supply into your power source.
For Optional Direct DC Power
●
Screw-on the DC power cable to the power connector on the modem.
●
Then attach the two wires at the other end of the DC power cable to a DC fuse/terminal block.
●
Connect the red wire to the "+" (positive) terminal and the black wire to the "–" (negative) terminal. Be sure the
GND connection is correct.
Warning:
Over-voltage protection is provided on the device. To ensure complete protection, you may want to add
additional filtering to the DC input.
Note:
For automotive application: according to the type of application, you can use permanent “+” or key-switched
“+” source. Connect the power supply to its source (for example, in a mobile situation, to the vehicle’s DC
fuse/terminal block).
