First and foremost, I arrived to radio from a mountaineering background rather than the other way around. I had my first exposure to radio when I was a kid, but it wasn’t until after university (Telecom Engineering btw) that I had the time and resources to properly dive into the hobby. Now that I’m licensed, SOTA feels like the perfect overlap between my two passions.
So I’m currently putting together a SOTA setup to operate SSB on 20m and 40m (CW is still a work in progress for me). The thing is, the kind of summits I enjoy the most—especially in winter—tend to be relatively technical peaks with very limited space at the top. Think of places like Peña Vieja in the Picos de Europa, Tebarray in the Pyrenees, or Espiguete.
In addition, these are usually trips where I either bivouac or stay in a refuge, so weight and pack size are absolutely critical — both for the radio gear and the antenna system.
When I try to picture myself deploying a 20m EFHW on some of these summits, I struggle to see how I’d do it given the lack of space and exposure. So before I get to building and adapting an antenna specifically for SOTA use, I’d really appreciate your advice:
Would you recommend an EFHW or an inverted V dipole in this kind of environment? For context, I think I’ll be using a 6m telescopic mast.
Regarding the rig, I decided to start using a G90 with a 12V 6Ah battery since it seems like a good trade-off between power, weight and capacity.
Thanks in advance for your insights, and looking forward to learning from your experience.
Focus on learning CW and this will drastically reduce your antenna requirements. You can use a vertical connected directly to your radio (something like the Elecraft AX1). It will be a compromise, but if the bands are in decent shape you will make QSOs.
On a few space restricted summits that had steep drop-offs (basically a cliff) I have had success with just letting my wire antenna dangle over the edge.
In my experience, it was almost always possible to deploy a full-size inverted V EFHW for the 40/30/20m bands, even on “pointy” summits – at the very least somewhere along the ridge used for the ascent (within the AZ of course). But sometimes, it was a question of available time and nerves to climb/scramble along an exposed ridge multiple times to put up and take down the antenna, and perhaps also the presence of other climbers that may be inconvenienced by it.
In summer, I usually make the effort to put up a full-size antenna, so that chasers have a better chance at hearing me. In winter when ski touring, or in summer on very long alpine routes with glaciers etc., time and weight constraints are often tighter. Then I resort to “quick and dirty” solutions like an AX1 on a KX2 (handheld), or even my KH1 – better than nothing, and has never failed to get me more than enough QSOs in the short time available.
Even on the summit with the smallest activation zone in HB, I could have envisioned installing an EFHW somehow, but climbing a ridge of a neighboring summit (for fun) for 6 hours first, and a long descent via a glacier meant that there was no time for that, so the KH1 + whip antenna it was.
My advice would be: on peaks/ascents where you can afford the time and weight, a trap EFHW made of lightweight wire (I like Poly-STEALTH 26 with Pico Traps) as an inverted-V on a ~6 m carbon mast is a good choice and makes chasers happy. I would not recommend a dipole on technical summits because of the additional hassle/weight with long coax, center balun etc.
When time and weight are everything, then go with whip antennas, or perhaps hang a wire vertically from your mast with one or two counterpoise wires, and use your ATU.
Of course the G90 is a pretty heavy rig for SOTA in my opinion, and a 6 Ah battery will give you several hours of operation at full power, so you could save a lot of weight by bringing a smaller battery (and/or a lighter rig ).
I am using a homemade 40/20 m efhw. It is a clone of the PAR end fed trial (vibroplex). The length is about 13 m, weight 135grams with the balun. I usually install it as an inverted V, eventually as a sloper, using a 6.3 m chinese fiberglass pole, 43 cm collapsed, 265 grams. This is my standard antenna, ok for almost all the summits I activated. It is fast and simple to install, it gives me very good results, I get good reports.
For very small summits, I used a Komunica hf pro 2 plus T. Collapsed, about 30 cm, weight, about 300 g. You will need in addition some kind of tripod, and a few radials. This is a shortened antenna, the results are far less vs the efhw. I would recommend this antenna only for very exceptional cases.
If you can install your 6m vertical pole, on a small summits, a wire along the pole, and a wire on the ground, + atu, will give you better results vs the Komunica.
I just wanted to ask Manuel HB9DQM whether he tried any of that on his high-mountain activations (lying on the ground or just tossing it over the ridge). I guess this only works when you are on rocky ground. On grass ground, especially when wet, this will probably not work. I remember one time when I was on such a grass summit I heard a light thumping noise. I didn’t pay much attention as reception was quite ok, but nobody wanted to answer me. Turning around, I saw that my antenna had collapsed and the wire was on the ground. Luckily, no tourists or cows were hurt.
Well, this looks like a POTA setup to me. Heavy and bulky. When it comes to technical summit, maybe you should have a look at lightweight rigs such as QMX, trusdx etc.Together with a little 1.5 Ah LiPo battery and that’s enough, 300g all together.
Antennas … Not easy. A 5m Chinese whip and a few radials will give you 20m and all the bands above. Works great. Small footprint. You can add the coil and you have a compromised 40m, still usable.
As said above , a full EFHW can sometimes fit in much more places than we think. You can build one with some coils, as a sloper, it’s smaller…
Hi Mike, welcome onboard, you’re not gonna regret the combination of mountain + radio!
This reflector is a good point to ask and sure you will get useful answers.
According yo your statement, you’re thinking on a suitable gear for winter/ overnight/ small summits… I guess you’d need space to carry drinks + food and warm extra clothes etc
You better get a reduced, but trusty gear then….
Rig: G90 is an affordable rig but too heavy for such conditions. I’d rather go for a QMX with a small batt (3 X 18650 cells), doing well in SSB with a reduced current draw and handy.
Antenna: 5m carbon rod + small trapped EFHW (abt.12m) is okay, but when space and other mountaineers in summit are the key point I’d go by a shortened vertical. I made a small 3m on a glassfiber telescopic pole that runs well in 20m /acceptable in 40m, with a few short radials on ground (some hints here). It’s very unobstrusive. I find the telescopic metal whips are heavier and are not okay for placing the center loading coil as per my design …
The Chinese whip is a 5.6m stainless steel whip, that you can buy from ali*** for 20€. It has a base, a ground spike, and a few radials. Deployed in 2 min. You can throw the radials in the cliff if they are too long. You might need a few guy lines if the snow is deep and fluffy.
There is a topic on the forum already if you want to learn more about it
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