This month our radio club decided to all try out Winlink for VHF. Here are some of the things I learnd while trying it out this month.
I did a big closet clear out during the pandemic and gave away / sold a bunch of my older ham hear including my physical TNC, a Kantronics KPC-3. I have a couple signalinks and have had some luck in the past with direwolf so I decided to sell my old physical TNC and associated radio.
We have a new VHF Winlink node in San Francisco, in addition to the nodes in Marin and Oakland. I was hoping I’d have decent luck being able to hit it with my 5 watts from my ft-817.
I decided to build a Winlink station using my Yaesu FT-817, a Signalink and Linux. To get access to Winlink I tried out both Winlink Express under Wine and Pat under Linux (which requires AX25 support)
My existing laptop had GalliumsOS which has been very nice for a few years, but I found that I couldn’t get AX25 support running there (there was some notes of some kernels with it built in, but I couldn’t track them down easily)
I tried a couple other distros and found that Fedora Workstation ships with AX25 kernel support (though you need to explicitly load it)
Here’s what I learned:
- High power radio is best, my ft-817 5w QRP for QRP or HF just doesn’t cut it. I couldn’t make contact with any of the VHF nodes though I could get into APRS digipeaters and a local Packet BBS
- Choose Windows over Linux. While I managed to get the software side installed on Linux, the Linux AX25 framework and tools feel fragile. Good to understand and “work” but don’t really seem useable in an emergency or for “sometimes” use. Seems like it would be fine for a dedicated 24/7 connection.
- Real TNC vs Signalink? Kind of a toss up. I never had any problems with my physical TNC under linux but the sound card interfaces are a bit fragile and cause port issues on start/stop of the interface or direwole. Nothing that isn’t unsurmountable but a level of complexity that’s annoying for “once and a while” usage. I know I could probably do more configuration to force reuse of ports, but couldn’t find an easy recipe….
- I wish I kept my KPC-3, it “just works” and its one less thing to configure under Linux.
- ‘axcall’ vs classic terminal program: axcall works but doesn’t seem as useful and stable as the classic serial terminals I’ve used.
- A VHF/UHF win link node would be a great addition to the East side of Twin Peaks. I can’t seem hit or hear any of the East Bay, Marin or Sunset nodes.
- I would likely dedicate a machine to Winlink only if I set this up permanently instead of trying to have it support aprs, classic packet and HF digital modes
For AX25 under Fedora Linux I found the following useful:
I installed the latest Fedora Workstation on my latop
I needed to load the ax25 kernel module using the instructions at http://xastir.org/index.php/HowTo:AX25_Fedora (the part near modprobe -a ax25)
I watched the two parts of this walkthrough of the install of the various parts of pat / direwolf https://www.youtube.com/watch?v=oZJJLfVz23k
I followed along here for the VHF parts (ignoring ARDOP etc…) https://rockfloat.com/ham/pat_linux.html
In the ax25.service file I used the following since I have a Signalink instead of a physical serial port. Direwolf creates the /tmp/kisstnc device
ExecStart=/usr/local/bin/ax25-up /tmp/kisstnc wl2k 1200
instead of
ExecStart=/usr/local/bin/ax25-up /dev/ttyUSB0 wl2k 1200
Hope this helps you.
I’ll likely try this again with my Kenwood TM-D710 and ty it with high power and see how it goes.
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