Is Packet Radio Still Around?

At a recent ARESLAX meeting we went over how to set up Winlink (email over radio) using handheld radios and laptops. I soon realized that the basis for this type of communication is AX.25 packet radio which I used to run in the late 1980’s. The Terminal Node Controller (TNC) pictured above is what you needed back then to interface the computer to the radio. I had a similar TNC back in the day.

Today a popular way to get into packet radio is to use a Signalink device. This is a relatively low-cost piece of hardware that is essentially a stand-alone computer sound card that is customized for use with radios. You choose a cable that connects to your brand/model of radio and the other side plugs into an RJ-45 jack in the back of the Signalink. Then a USB cable connects the Signalink to your computer.

Once your radio is connected to a computer through the Signalink interface you can run a program called Soundmodem (from This program uses the soundcard to send and receive AX.25 protocol data from the computer. Additionally, using a program called EasyTerm (available from the same website) you can connect to other packet radio users in your area via the radio.

That’s the most basic setup and just the tip of the iceberg. From here you can load software to use Winlink to send email across the radio and the internet. Even when your local infrastructure is completely down. VARA FM can be used to increase your data rate with Winlink in both VHF and HF bands. Another aspect is APRS. APRS is a way to track position coordinates of your amateur mobile station, your home station, or your location if you’re out hiking with your HT. A lot of people run home Weather Stations and send the data through via APRS.

So, as you can see, packet radio is alive and well. I’ve been immersing myself back into it for the last few months and I feel like I’ve barely scratched the surface. One of the reasons is the integration with the Internet that we did not have the luxury of having in the late 80’s. As I learn more about it, I’ll update this post.

  • david
  • Ham radio operator for many years