APRS Fun - A new digipeater in Lawrence

I spent some time over the last couple of weeks attempting to get APRS working on my radios. And I found that Lawrence did not have a working digipeater or igate. I asked on the W0UK Radio club email list, and a couple of people were able to verify that we did not have one working anymore.

So, I put it on my workbench. I was going to build a digipeater.

I spent some time talking to Claude.ai, and we came up with a plan to use some of the equipment that I already had laying around:

  • A Lenovo ThinkCentre M700 tiny computer
  • A Baofeng UV-5R Mini
  • Ubuntu Linux server 24.04 LTS
  • Direwolf software

I started out getting the ThinkCentre set up wtih Ubuntu Server. I installed 24.04 LTS. LTS stands for “Long Term Service”, and is great because it is supported for five years. The kernel and packages don’t get major changes that could break some applications.

The ThinkCentre has 12Gig of RAM, and a 256 Gig Samsung SSD. Plenty of space for the project.

Once the server was installed and fully patched, there were some applications and packages to install.

’ sudo apt update && sudo apt install -y git gcc g++ make cmake libasound2-dev libhamlib-dev libgps-dev portaudio19-dev'

Direwolf was installed by pulling the code from Github, and compiling. While there is a package in the Ubuntu repositories, it is sometimes and older version.

’ cd ~

git clone https://www.github.com/wb2osz/direwolf

cd direwolf

mkdir build && cd build

cmake ..

make -j$(nproc)

sudo make install'

I had to have the GPS coordinates of my house, due to the fact that I didn’t have a GPS dongle for the server. Easy to find.

The Baofeng UV5Rmini needed to be set up so that it was on APRS: 144.39 MHz. Initially, I had it on the wrong frequency, and it wasn’t hearing anything. Easy fix though.

Once on the correct frequency, Direwolf was able to hear my Anytone 890 radio that was beaconing on APRS!

I decided to take a break, and take my dog out to Clinton Lake for a run on the hill. I took my Anytone 890 with me to see how far I could get away from the igate and still get picked up.

It turns out…not very far. The UV5Rmini with a stock antenna, indoors, would not pick up the radio once I got out of the neighborhood.

But..the Digipeater is working. A different antennal will help. And, maybe we find a new home for this set up so that it can benefit all of Lawrence.