Fasten your seat belts for FT8 @ camp

Early in the morning of the day that my XYL and I left for our most recent camping trip I was making a quick pass through some of my favorite Amateur Radio blogs and came upon a post by Bas, PE4BAS and another post by John, AE5X regarding the new WSJT protocol\mode, FT8. In John’s post he graciously referenced my recent post on PSK31 with my KX2 as an example of QRP portable digital operation. I had already packed my equipment in order to operate PSK31 from camp but I thought that I may as well try FT8. I pulled out my PC and installed the beta version of WSJT-X. I didn’t have enough time to setup the KX2 to check configuration and test so I figured that I’d just wing it at camp.

The second day at camp dawned bright and beautiful, perfect weather for digital operations. After a nice breakfast I pulled out my equipment to have a go at FT8. I quickly placed one end of my LNR EF-Quad well up in a tall fir tree and setup the KX2 and laptop. When I originally setup for PSK31 with my KX2 I used an older Toshiba laptop however the battery in that laptop would not hold a sufficient charge so I switched over to another old laptop that I purchased a few years ago at a local Hamfest with the intent of setting up a dedicated WSPR station with my IC-718. This never happened and in the face of my new WSPRlite transmitter it’s not likely that it will so I decided to use it as my portable digital PC. It is a bit more compact than the other laptop and as a result the keyboard is a wee bit smaller, but it’s still reasonably serviceable.

In order to confirm that everything was setup correctly as far as the general PC\radio interface I made a quick test with Fldigi and PSK31 using the same USB soundcard I described in an earlier post. This resulted in a couple of very nice QSO’s with N1ZQ who was operating portable in the White Mountains of New Hampshire and KA3OCS in Virginia. Both stations were very considerate of me being new at PSK31.

Fldigi PSK31 @ camp

With general functionality confirmed I shut down Fldigi and started up WSJT-X. Within a minute I had the interface to the radio and audio setup, selected FT8 on the Mode menu, and with a click of the Monitor button WSJT-X was receiving and decoding FT8 on 20m.

WSJT-X FT8 @ camp

WSJT-X configuration was as follows with the KX2:

WSJT-X radio config with KX2

WSJT-X audio config

This was my first experience with WSJT-X having never operated with either JT9 or JT65 in addition to the new FT8 mode. If you’ve not seen FT8 in action before, let me tell you that it moves very very quickly. The Band Activity pane filled quite rapidly and scrolled along at a rather brisk pace. I observed the activity for a wee bit to get a feel for the flow of activity and then attempted to respond to some CQ calls. After a few attempts I was rewarded with my first FT8 QSO, N4ULE. It was over before I knew it!

First FT8 QSO, N4ULE

When it comes to FT8, as Briscoe Darling once said, “Just jump in where you can and hang on…”

In fact if there was a theme song for FT8, it may well be Doug Dillard playing “Banjo in the Hollow” as in the video. FT8 moves right along, just like Doug’s pickin’.

The KX performed as expected, flawlessly. The CAT interface with WSJT-X functioned without an issue. The KX2 mode was DATA A. I’ve read a number of threads on the heat sink temperature rise with digital operation with the KX2\KX3. In the KX2 manual Elecraft states to reduce power to 5W so that is where I set the power. Depending upon the ambient temperature and operation my KX2 sits around 21-25 C. It was about 78 F\25 C at camp and I saw the heatsink temp peak at around 34 C after several rounds of transmission. It would quickly rise and as quickly descend at the end of each transmission. I don’t know what the foldback temperature is for the KX2. I will monitor the power output with my OHR WM-2 the next time I operate FT8 and digital modes in general to see if I hit the foldback in normal operation.

Given our position in Cycle 24, recently purchasing a shiny new QRP rig might not have been the best timing but digital modes seem to be on the rise. They mostly certainly provide new opportunities to make contacts and expand the frontiers of Amateur Radio. Like all of the other modes, some old, some new, they are another tool in the toolbox. My initial impression of FT8 is positive and while it will take a little practice to get used to the pace, my guess is that there will be some more operation with FT8 and my KX2 in the future.

UPDATE: Bas, PE4BAS asked a good question in the comments, that being time synchronization for the PC. I forgot to add this into the original post. WSJT-X requires a means for synchronizing the computer clock to UTC within ±1 second. Thankfully my XYL’s cellphone has service when we are at camp so I used that to access the US Naval Observatory time service at http://tycho.usno.navy.mil/simpletime.html. Using this reference I updated the PC clock manually. Lacking a data service I would have used WWV. This Genesis Radio site has a very nice list of time signals around the world. If the PC was connected to the Internet I’d use NISTIME 32 (scroll to the bottom of the page for the download), which is what I use on my home QTH PC.