Step-by-step guide on building your own Tetra gateway based on the SvxLink platform:
Disclaimer:
Before proceeding, it is important to acknowledge that constructing a Tetra gateway, with or without SvxLink, necessitates advanced soldering skills, understanding of pinout schematics, hardware manipulation, and software programming. Follow safety protocols to prevent any potential damage or harm. Please note that we are not liable for any loss or damage incurred by you or your equipment during the undertaking.
What You’ll Need:
Mobile Tetra Radio:
– Motorola MTM800, MTM800e, MTM800FuG, MTM 5200,MTM5400, MTM5500
– Not compatible with SRG3900 or portable radios
Portable Radio
– Needed to establish communication with the Tetra gateway’s donor radio on the Tetra network.
Raspberry Pi or Debian Machine:
– Raspberry Pi 3B or newer recommended
– Raspberry Pi Zero W
– VM under Debian over Ubuntu or other distributions.
– Minimum 2 USB ports and Ethernet connectivity
FTDI 3.3V RS232 to USB Cable
– Used to connect the Tetra radio to the Raspberry Pi
– Solder connectors onto the cable ends for MTM800e
You may also need the FTDI driver installed on your machine.
You can download that here: FTDI cable driver download
Signalink, R1 2020 interfaces, or CM108 Sound card:
– Required for audio and PTT (Push-To-Talk) functionality
– Signalink is the easiest option
Antenna and Power Supply:
– Suitable antenna mounted as high as possible
– Super low-loss coaxial cable
Tetra Branch of SVXlink Software:
– For Raspberry Pi, download the SvxLink image
– For Debian, download from the project’s GitHub page
#Setting Up Raspberry Pi:
For Raspberry Pi users, it’s as simple as writing the download image (Download from here – scroll towards the bottom of the page to find the link) to your 8GB (or larger) SD card, inserting the card into your Pi and booting it up.
To write the image to your SD card, you’ll need a copy of Raspberry Pi Imager tool.
Once you have written the image to the SD card, insert it into your Raspberry Pi (3B or newer), boot the Pi, wait aprox 5 minutes and then check your routers DHCP address lists to locate the IP of the Pi.
Then, using your favorite SSH tool, SSH into the Pi on port 22 using default username: pi and password: raspberry
Be sure to check for software updates after connecting to the Pi, with the usual commands:
sudo apt-get update
You can then check for SVXLINK updates using the following commands (this is important as the software is updated regularly):
sudo systemctl stop svxlink
cd /home/pi/svxlink/src/build
sudo git pull
sudo make install
sudo systemctl start svxlink
Connect via SSH:
– Locate the Pi’s IP address from your router’s DHCP address list
– SSH into the Pi using default credentials
Update Software:
– Run software updates for Raspberry Pi OS
# Setting Up Debian:
The below steps include the installation of debian packages, which at the time of writing are the current available versions. When you go to install these packages, you may find that they have been replaced with a newer version. to locate the newer version, google “apt-get install PACKAGENAME” and replace the package name below with the updated name.
You will find the most up to date installation steps available here
Install steps:
sudo apt-get update && sudo apt-get install g++ libsigc++-2.0-dev libgsm1-dev libpopt-dev tcl-dev libgcrypt20-dev libspeex-dev libasound2-dev make alsa-utils git cmake libqt4-dev libopus-dev opus-tools libcurl4-gnutls-dev libjsoncpp-dev
sudo addgroup –gid 496 svxlink
sudo useradd -r -g daemon svxlink
wget https://github.com/dl1hrc/svxlink/archive/refs/heads/tetra-contrib.zip
Unzip tetra-contrib.zip
Cd /svxlink-tetra-contrib/src
mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr -DSYSCONF_INSTALL_DIR=/etc -DLOCAL_STATE_DIR=/var ..
make
make doc
sudo make install
sudo ldconfig
cd
cd /svxlink-tetra-contrib
Mkdir sounds
Cd sounds
wget https://github.com/sm0svx/svxlink-sounds-en_US-heather/archive/refs/tags/19.09.tar.gz
tar -xf 19.09.tar.gz
sudo mkdir /usr/share/svxlink/sounds/en_US
sudo cp -a 19.09/* /usr/share/svxlink/sounds/en_US (check the file path of the source files)
You can then check for SVXLINK updates using the following commands (this is important as the software is updated regularly):
sudo systemctl stop svxlink
cd /home/pi/svxlink/src/build
sudo git pull
sudo make install
sudo systemctl start svxlink