Every year in October, emergency communication team members and leaders get together for the annual Wisconsin ARES/RACES conference. This year’s conference, the 19th annual held, featured the theme of Digital Communication. Digital is a big subject and a one day conference can barely scratch the surface. The presenters did an excellent job at highlight the key points and moving the discussion forward on a greater use of digital communication for emergency communication.

Joe Schoebel KD9CJX and Michael Martens KB9VBR giving their presentation on HF digital for Emergency Communications (Photo by Kathy Schramm)

Now I must admit that I was one of the presenters at this year’s conference, so I may be a bit biased. But I believe this was one of the best emergency communication conferences that I’ve attended in a long time.

HF Digital Emergency Communication

In our presentation on HF Digital Emergency Communication, Joe Schoebel, KD9CJX, and myself ran down a list of common HF digital modes that are currently in use with an eye towards their emergency communication potential. Most of the modes you hear on HF are limited in their utility: weak signal modes like JT65 or FT8 are great for making the contact, but they lack the ability to convey longer messages. Keyboard modes like PSK31 or RTTY are better suited for transmitting longer text files, but lack error correction, so rough band conditions can affect the readability or copy of the message. A better choice for HF digital is Winlink.

Winlink is a global radio email network that allows you to send and receive email over the radio using a familiar interface. If you’ve used Winlink in the past, it may have been over the VHF airwaves using a packet radio modem or TNC like the Kantronics KPC-3 or MFJ 1270. This is great for short range communications and interfaces amateur radio to the Winlink Internet email network, but Winlink isn’t just for VHF, it also has a robust HF interface.

Email via the HF bands is great for situations where Internet access isn’t available- like for maritime activities. But HF email via Winlink is slow. The commonly used Winmor protocol runs between 300 to 2500 bytes per minute based on the amount of bandwidth used. But the protocol is error correcting, so messages are transferred with 100% readability. You can achieve faster Winlink transfer speeds with the PACTOR protocol, but that system requires purchasing an expensive radio modem. Winmor is open source, so no extra equipment, besides a sound card interface like a Rigblaster or Signalink, is required. So if you’ve played around with other digital HF modes, you should have the equipment necessary to send and receive email via Winlink.

For a demonstration on the Winlink system and the Winmor protocol, please view the video below. I take you through the steps of drafting a message and sending it via HF.

Is Winlink the best method to send and receive emergency communication messages? Maybe not. If you are in a situation with limited resources, you may not have enough power to run the laptop computer necessary for the application. Voice communications may also be more expedient for certain types of messages. But Winlink is a viable solution for emergency communications and if the Internet is unavailable in your location, the global Winlink network will get your email messages out of the affected area and into the Internet stream. My recommendation is that you familiarize yourself with Winlink, and other HF digital modes for that matter, so you will have the capability to use them when the need arises.

Do you have any experiences with Winlink or other digital HF modes for emergency communications? Please leave them in the comments below.