APRS iGate from a Raspberry Pi Zero
A few years back I tried to create an APRS iGate using an RTL-SDR Dongle and a Raspberry Pi 3. I watched a few videos and read through at least a dozen online posting and documents. However, I never really got it working correctly. It would post it’s status on APRS.FI but it never registered any check-ins from other APRS devices. Eventually I decided I needed the Pi 3 to make a Hot Spot for my D-Star and DMR radios. So the iGate was retired.
2 weeks ago I ran across an article on making an APRS iGate using a Raspberry Pi Zero W. The Pi Zero W is an inexpensive unit and I still had the RTL-SDR Dongle in the work bench. I am not going to go through that process here since others have done it. However, I will point you to the on-line resources I used, a few things I ran into and the parts I used to get it working. There are other options for RTL-SDR Dongles, Raspberry Pi Zero W kits and other parts. I am just going with what worked for me. Your Mileage May Very!
Here is a list of parts I used. You might already have some of them in your parts box or PC supplies. (Links and pricing at time of article – 20190519)
- Raspberry Pi Zero W Basic Starter Kit – $26.99 – Includes Mini HDMI to HDMI adapter and Micro USB to USB adapter.
- RTL-SDR Dongle with Antenna – $29.95
- Samsung 64GB Micro SD Card – $11.99 – You need a minimum 16GB micro SD card. This was overkill at 64GB but it has great ratings, is pretty cheap and I already had one in my parts box.
- Extra parts I used to help setup the Pi.
- 4 port USB unpowered hub – $8.24 – Any USB hub will work as long as it has 3 or more ports. You will need to connect a keyboard, mouse and the RTL-SDR Dongle.
- USB to Ethernet Adapter – $13.99 – You probably won’t need this as once you are at the screen interface, you can select your wifi and connect. I was having an issue with getting it on my wifi so I went Ethernet for the initial setup.
This is the article I based most of my installation from: Updated guide to setting up an APRS RX only iGate using a Raspberry Pi, RTL-SDR dongle and a pre-built image.
The article was written by Keith Maton, G6NHU. I am sure it took a lot of time and effort to put the information together and make an SD Card Image. The fact that he made the SD Card image is what really makes this process doable. Thanks Keith.
Following the article I was able to get the Pi up and running but I did run into an error when testing.
Signal caught, exiting!
User cancel, exiting…
Luckily, Keith had this covered as well. Right after the test, he listed the above error and indicated that you needed to backup your settings, delete Direwolf then download and compile it. The instructions worked great and the iGate started working.
I did run into an issue with the instructions to auto start Direwolf on boot up. It says to run:
sudo systemctl enable direwolf
This gave me an error and I am wondering if that process has changed since the article was written? So I found the documentation for the Direwolf program at: Direwolf User Guide
On page 27 & 28 it describes how you can run a job from Cron that will start Direwolf on Boot.
My suggestion is to run this script from cron so if direwolf stops running for any reason, it will be
automatically restarted. Use the “crontab –e” command and add a line like this, substituting you own
user name instead of john:
* * * * * /home/john/dw-start.sh >/dev/null 2>&1
The line above will run the /home/john/dw-start.sh script once per minute. Dire Wolf will be started
automatically if not running already. If a previous instance of Dire wolf crashes, or is terminated for any
other reason, it will be restarted within a minute. A log of restarts can be found in /tmp/dw-start.log.
dw-start.sh will try to determine if you have a graphical desktop and select either GUI or CLI mode.
When I ran crontab -e, the command listed above was already there, just commented out. I removed the # sign from the beginning of the line, saved my changes and rebooted. Less than a minute after it rebooted, a terminal window appeared, Direwolf started and connected the iGate to the Internet.
It probably took me an hour to put this all together. I am sure I could do it in half the time now that I know the procedure. I think this is a very doable project for anyone that wants to setup an iGate at home.
I am not sure that I could answer any technical questions but if you have any, please post them here or use the Contact JohnnyF form. I will do my best to answer them, if I can. Hope you found this posting useful. If so, good luck with your iGate project.
73, John, WJ0NF