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Table of Contents
QtSoundModem (QtSM) is a multi-platform port of UZ7HO's Sound Modem - a software modem that uses a computer's sound interface to send and receive AX.25 data, known as packet radio. It supports various baud rates from 300 to 4800 baud and modern extensions like FX.25 and IL2P, and if you already have a suitable sound interface and method to trigger a PTT its a quick and easy way of getting started with packet radio without having to invest in a dedicated TNC.
Note that QtSoundModem only handles the modulation and demodulation of the data. To interact with another packet station you'll need a packet terminal like QtTermTCP
Installation
Windows
The instructions were tested on Windows 11 but presumably work on other versions.
First off if it doesn't already exist, create a directory in your Documents directory and call it something like “Packet Radio Software” or similar.
Download QtSoundModem.zip
Extract it, and copy the “release” directory to the newly created directory, then rename it to something useful like QtSoundModem.
To access if from the Start Menu, Find QtSoundModem.exe, Right Click it, and select Pin To Start.
Optionally if you want to create a desktop shortcut, you can also Right click the exe again, select Show more options > Send to > Desktop (Create Shortcut)
This completes the installation. The first time you run it you may get a message that Microsoft Defender SmartScreen prevented an unrecognised app from starting. Click “Run anyway”
Configuration
Setup Devices
Go to Settings > Setup Devices
