User guide
Table of Contents 
Multi-Tech Systems, Inc. MultiModem CDMA Wireless Modem User Guide  3 
Contents 
Chapter 1 – Product Description and Specifications ................................................................................................ 4 
Product Description ................................................................................................................................................. 4 
Safety ...................................................................................................................................................................... 5 
General Safety ................................................................................................................................................. 5 
RF Interference Issues ..................................................................................................................................... 5 
Installation Instructions for Hazardous Locations ............................................................................................. 5 
Vehicle Safety .................................................................................................................................................. 5 
Maintenance of Your Modem ........................................................................................................................... 6 
Your Responsibility .......................................................................................................................................... 6 
Package Contents ............................................................................................................................................ 6 
Specifications .......................................................................................................................................................... 7 
Functions – CDMA Modes ...................................................................................................................................... 8 
Electrical Characteristics ......................................................................................................................................... 8 
Antenna/RF Specifications ...................................................................................................................................... 9 
Interfaces ................................................................................................................................................................ 9 
LEDs ....................................................................................................................................................................... 9 
RS232 15-Pin Connector Pinout ........................................................................................................................... 10 
AT Command Information ..................................................................................................................................... 10 
Chapter 2 – Activation and Installation .................................................................................................................... 11 
Activate Your Wireless Account ............................................................................................................................ 11 
Hook up the Antenna, Serial Cable, and Power .................................................................................................... 11 
Optional – Attach the Modem to a Flat Surface .................................................................................................... 12 
Install the Modem Driver ....................................................................................................................................... 13 
Chapter 3 – Using Your Wireless Modem ................................................................................................................ 18 
Phone Numbers for the Wireless Modem ............................................................................................................. 18 
Examples of Useful AT Commands ...................................................................................................................... 18 
Verifying Signal Strength ............................................................................................................................... 18 
Checking Network Registration and Roaming Status ..................................................................................... 18 
Checking the Modem’s Identity ...................................................................................................................... 18 
Establishing a Voice Call ............................................................................................................................... 19 
Establishing a Circuit-Switched Data (CSD) Connection ............................................................................... 19 
Answering a Circuit-Switched Data (CSD) Connection .................................................................................. 19 
Using Short Message Services (SMS) .................................................................................................................. 20 
SMS Examples .............................................................................................................................................. 21 
Internet Access ..................................................................................................................................................... 22 
Connecting to the CDMA Network for Internet Access .................................................................................. 22 
Mobile PhoneTools ............................................................................................................................................... 23 
Chapter 4 – Troubleshooting and Frequently Asked Questions ............................................................................ 24 
Troubleshooting Examples .................................................................................................................................... 24 
Situation A: The modem does not respond through the serial link ................................................................. 24 
Frequently Asked Questions ................................................................................................................................. 24 
Appendix A - Cables .................................................................................................................................................. 27 
Data Cable Diagram – No Voice .................................................................................................................... 27 
Data Cable Diagram – with Voice .................................................................................................................. 28 
Fused DC Power Cable Dimensions .............................................................................................................. 28 
How to Change the Fuse ............................................................................................................................... 28 
Appendix B - Waste Electrical and Electronic Equipment (WEEE) Statement ..................................................... 29 










