Multi-Tech MTC-LNA4 Install Guide

NOTE: The MTC-LNA4 modem requires WIN-911 version 4.20.5 or newer. If you're unsure which version of WIN-911 you have, open WIN-911 Workspace and navigate to System > Info and you'll see the Release Version. Older versions of WIN-911 do not display a Release Version, if that is the case, you can check to Add/Remove Programs for the version number of the WIN-911 Navigation module.

NOTE: If you are looking for the WIN-911 V7 Install Guide, it is located here.

NOTE: If you are looking for the WIN-911 Standard/Interactive/Advanced Install Guide, it is located here.

This guide will walk through the installation and setup of the Multi-Tech's MTC-LNA4 using a serial cable with an RS-232 to USB converter. We DO NOT recommend using the USB version of the LNA4. 

A. Activation / SIM Card Info

Before configuring WIN-911 to use your modem, you will need to set up a wireless account with a cellular provider and obtain a Standard SIM card. 

The MTC-LNA4 supports both AT&T and Verizon. By default, the modem is configured for use with AT&T. If you'd like to use Verizon, you will need to manually change the modem configuration for use with Verizon. You will find more information below. 

WIN-911 will potentially send many text messages so we recommend subscribing to an unlimited texting plan to avoid overage charges. Neither a data nor voice plan is required for use with WIN-911.

It is possible to install the modem ahead of time without a SIM card, but WIN-911 will not function correctly until the SIM card is installed.

Installing a SIM Card 

Slot for SIM Card

Once you have your SIM card, you can install it into the modem.

NOTE: You can use a Micro or Nano SIM card but you'll need the appropriate Standard SIM card adapter. 

  • Locate the SIM card slot on the side of the modem. The slot is labeled SIM. 
  • Slide a SIM card into the SIM card slot with the contact side facing down as shown. When the SIM card is inserted fully, it will lock into place.
  • To remove the SIM card, push the card in and it'll eject from the device.

Modem Hardware

If you purchased your modem from WIN-911 Software, an antenna, power adapter, serial cable, and a Serial to USB adapter have been supplied with it.

  • Connect antenna to the Cell connector.
  • Connect the power supply adapter to the DC Power connector.
  • Connect the male end of the serial cable to the modem
  • Connect the female end of the serial cable to the Serial to USB adapter and plug it into your PC.
  • If your PC has a serial port, you can connect directly to it instead of using the USB converter.

Modem Configuration

After you have connected the modem to your PC using the Serial to USB adapter, you will need to identify the COM port that it has been assigned. 

  • Open Device Manager
  • Expand the Ports (COM & LPT) section
  • You should see USB Serial Port (COMX), where X is the COM port it was assigned

In this example, the modem was assigned COM3

AT&T Users

If you are using an AT&T SIM card, you won't need to configure the modem. Skip ahead to the Configure WIN-911 SMS Gateway section.

Verizon Users

If you are using a Verizon SIM card, you'll need to connect to the modem using a terminal program so that you can switch the modem to operate on Verizon's network. We recommend using PuTTY, which can be downloaded from here.

  • Download and run PuTTY
  • When PuTTY appears, select Serial for Connection type
  • Enter the COM port your modem has been assigned in the Serial line field
  • Change Speed to 115200

  • Click Open and a terminal window will appear
  • Enter the following commands and then press ENTER. (You may not see what you're typing until after you type ATE1 <ENTER>)
    • ATE1
    • AT#FWSWITCH=1,1
    • Enter the next command after you see +PACSP0 appear. It could take up to a minute.  
    • AT+CPMS=ME

  • Once you run the switch command, you can continue to the next section.

                                        Note: to switch the network back to AT&T the command is AT#FWSWITCH=0,1


Configure WIN-911 2021 SMS Gateway

In the WIN-911 Workspace, click on Gateways > "+" > SMS to create a new gateway. 

Enter a unique name for the modem. 


Select Serial for the Connection Type and enter in the COM port for your modem using the browse button on the right for Port.

Leave your radio type set to GSM and leave the Initialization field blank. WIN911 will automatically detect radio type.


Enable Incoming: When enabled, WIN-911 will process incoming SMS messages for the purpose of remote acknowledgment and Alarm / Report requests. 

Truncate messages to 70 characters: Both Verizon and AT&T allow multi-part text messages so you do not need to enable this option.

Click Test Settings to send a test message to a mobile phone. WIN-911 will also check the registration status, signal quality, and bit disparity rate of the modem. 


Select the Save Changes button to save your configuration.WIN-911 is now configured to properly use your modem. 


Technical Support

To create a support case, you will need either your Customer Care Code or your Serial number. You can create a Case online or contact the product support line: (512) 326-1011.