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DX S2S Plotting and Scheming


Is anyone in VK, ZL, JA, or anywhere else interested in trying to achieve some DX S2S contacts?

One of my New Year’s resolutions is to make this happen. I sometimes operate with 100W from summit, and I plan to build a Bobtail Curtain antenna for the project, most likely on the 20m band, given the current timing within the solar cycle.

I plan to work out the timing that will be optimal for each DX area and orient the antenna accordingly within a planned timeframe. Hopefully some of you will be interested in attempting to make contact.

CW is the most likely mode, though I’m happy to try SSB and/or digital modes as well if there is interest.

So let’s use this thread to start planning. Who’s interested in giving this a go? Where are you located and what mode(s) do you prefer? Anyone else in the US interested in making this a DX S2S QSO Party?



Sure. My only s2s with north America occurred last November on 17m CW at around 2200 UTC. I would be very happy to increase the hit rate with other activators who are keen to make it happen. I usually run 10w out but can run more from a 706 for a few hours if I know someone else is out there. I would not be the only VK interested.
Currently I rarely hear US activators in the 2000-0100 times slot.

Other than 30/20/17, I think 40m CW is a real option, I have worked into North America on 7 CW but the stations worked have been home/fixed stations on the west coast. But good conditions are needed, and the right time, which for 40m would be in the grey line at or near our sunset, approx 0800-1000 UTC at present (summer) but 0700-0800 in autumn/winter.
73 Andrew VK1DA/VK2UH


I think this is possible. On three recent activations I have worked multiple Japanese home stations running FT8 on 20 meters. I was only running FT8 at 5 watts with a linked dipole. All of these contacts were at 2100 to 2200 UTC. I think many of the activations in North America tend to occur earlier in the day and miss this window. I also can run higher power if I take my IC-7000 instead of my ft-817. I used this radio during the NA/Europe s2s event and worked two summits in Germany on 20m SSB. The time frame 700 to 800 UTC (12 am) would be an issue here since many of the local summits in the Phoenix area are in large parks or mountain preserves which are not accessible late at night.

73 Burke


I have only made 6 s2s with USA. I put a filter on my log here is the result.


Note the time the QSO’s were made probably represent a window of time we were both able to be on a summit as much as an optimal time for propagation. They also show don’t discount the higher bands.

John ZL1BYZ.


Yes, thanks John. I may try to come up with a simple way to make the bobtail curtain switchable to 17m somehow. Then again, 20m with some power and antenna gain may just work out.

The MUF for the path to ZL from California is definitely reaching 18mHz now, and sometimes pushing to 21mHz. Those bands are also nice and quiet.

Thanks for the data and the suggestions. Hope you’re able to join in on the fun when we give it a go.



Hi Adam, all

Yes I’d be interested in giving it a try. So far I have not worked any S2S with North America, probably because I haven’t been on a Summit at the appropriate time both for propagation and for the activators over there. My usual SOTA rig is the FT-817 but like Andrew VK1DA I also have an Icom 706 that I can use for a limited time. It kills the batteries pretty quick with its 1.6A on receive!

Location here is southern NSW so I have easy access to some 10-point VK2 and VK3 Summits. I prefer CW but have been known to plug in a microphone and try SSB occasionally, if signals are strong enough. I don’t have any digital mode capability at the moment. I have antennas for all HF bands from 160m to 10m and am happy to try any or all of them, though if it looks like 160m is possible I’ll need a bit of notice… I’d probably put the kite up for that one, with an end-fed half-wave under it, and that needs a lot of obstruction free real-estate on the Summit.

I’ll keep an eye on this thread for further developments.


Bernard, VK2IB


I have made 1105 contacts with USA SOTA activaor stations from my home QTH, in the last 2 and half years. I can tell you that 17 & 15m signals are consistently better when the activator operates those bands and I can compare signals from the same activation regardless of the MUF. I have observed this both activating and chasing here in ZL. I wonder if the low SOTA antenna’s used gain some efficiency at higher frequencies as their height even though low becomes more significant on the higher bands.

The four hour time slot between 20:00 and 00:00utc has been the most reliable with probably about 80% of those contacts been made during that time. Certainly seems to be a mutually suitable time to be on a summit at both ends.


Hi John. Yes, in theory at least, a portable antenna on top of a mountain would put out a much better signal than the same antenna lower down. I recall reading an interesting article by Les Moxon G6XN about using sloping terrain to produce some gain using a simple inverted-V dipole. I’ve not deliberately tried to exploit that but thinking back to some of my activations I can recall occasions where signals came in much stronger from the downhill direction than from other points of the compass, sometimes dramatically so.

So I guess it would be smart to orient our antennas so as to take advantage of that effect. Pick a Summit with a steep slope falling away in the direction you want your strongest signal to go, and set up your antenna right on the edge. Moxon said he tried it using a fishing pole to push his antenna out over the edge of a cliff, but I don’t know that I’d recommend that. Not for the faint-hearted, anyway!


I was meaning height above ground from the same location, only thing changing is frequency. What I have observed is better SOTA DX performance from the same antenna at the same location on the same day but higher in frequency. This has been quite obvious many times over several years. It seems counter intuitive in these days of low solar conditions that signals on 17 & 15m have been better than 20m from the same activator station during the same activation.


I made many SOTA contacts with ZL1BYZ from California with 5w and dipole.


I just had a nice S2S last night with JP1QEC/1 on 20m, from my summit in Arizona. I’ve only had a few S2S with Pacific DX including ZL1BYZ, JP1QEC, and JP3PPL. 17, 15, and 20m are usually the best when being chased although ZL1BYZ has worked me on 12 and 10m when I’ve been on summit. Always with an inverted vee, sometimes with 100w and others with 10w.

Later in the UTC day is the ideal time for propagation in that direction. Since many US activations take place in the 1700-1900UTC range, I think a lot of them miss the opportunity for DX to the Pacific (but of course that is usually driven by the fact that we usually want to be off the mountain before dark - those of us on the West Coast have an advantage in being able to activate until later in the UTC day).

I’d enjoy a DX S2S QSO Party with that an S2S objective to the Pacific region. Hopefully if it happens I’ll be able to participate. Presumably it would occur on a weekend and it’s often harder for me to activate on weekends.

Watching this thread…

73 de Keith KR7RK


I dont know if the timing works but there will be many of out and about in VK3 on summits Feb 1, 2 & 3. I am planning on on tang FT8 with me. Happy to camp on a Summit to get the time right for both ends if that helps.


I’d like to try for an FT8 S2S with you - probably on 20m, between 0700 and 0900.


While it is too hot to activate here in vk5 i chase JP1QEC when he is activating. Most times from here I can not hear the USA stations He is working from the summit in Japan on 20m . I set up my antenna on my lawn and use kx3 as if i was activating a summit and I have more success on 17/15 m bands than 20 m my morning time around 23.00 utc. The only S2S I ever made with USA was on 17 m back in 2017 from memory on a morning activation around 02.20 utc. But who needs sunspots it still is possible and most likely on cw mode.
vk5cz …


Propagation in that 2000z-2400z window has been erratic for the last six months. I am 1000 km south of Tokyo. On 20/17/15 i hear the NA chasers more often than the JA activators. The north-south path is not good for me either lately. Hardly ever hear the old standbys in VK and ZL. Doing much more chasing on 40 than previously.
Steve in Okinawa