This morning, a member of a local contest club to which I belong reported noteworthy propagation to:
EU on 15 m and 20 m short path and
JA on 15 m long path
in the CWops Test from 0700 to 0800 UTC today. This was two to three hours before our local sunrise, an unusual hour to be working DX on 15 m.
At 0730 UTC, a little more than half the short path from eastern NA to central EU is darkness. Perhaps this is enough to circumvent the twin problems of the “F2 region diurnal summer anomaly” and “F1 blanketing of the F2 layer.”
The NA - JA long path, passing through the Southern Hemisphere and low latitudes of the Northern Hemisphere, avoids both problems.
Perhaps the best strategy for those in the NH looking to take advantage of “incredible DX propagation” now through the end of summer is to focus on to working the SH in general, NH via long path, and NH when the short path is mainly in darkness.
And, of course, one can hope to catch good sporadic E openings this time of year.
As far as NA-EU SOTA is concerned, the long path is a long way for a portable QRP signal, plus night isn’t usually our thing. 15 m and 17 m seem to be the best short path options at the moment. In the last seven days, I’ve worked nine EU SOTAs on 15 m and 17 m, and only one EU SOTA on other bands (10 m with QRO activator OE9HRV, who was barely copyable).
Here’s a website that visually illustrates what W3LPL &W4GO are describing: https://prop.kc2g.com/ Click on the MUF tab to see current MUF propogation conditions for your intended path.
I also find very helpful the eSSN tab which is confabulation of ionsonde stations. Interesting to note the impact of recent solar flares.
Guy/n7un
Here’s a very nice illustration of timing between a Solar Flare (xray) which impacts our ionosphere in 7 or so minutes and the subsequent CME debris “cloud” some 72-hrs later. From Paul/NA5N.
FDIM presentation. https://www.qrparci.org/resource/FDIM81.pdf
Guy/n7un
Hi Guy,
Nice diagram, the time between the first hit and the Plasma arriving 2-3 days later can create “pre-Auroral-Enhancement” on the HF bands, especially those above 10MHz. The problem at the moment is that, with so many CME hits one after the other, we don’t get to take advantage of PAE as the Ionosphere is already being battered by the next CME. Once all the storming dies down in a few days, hopefully, we will see the propagation enhancement shown by Paul’s 2nd [QRP] indicator on the bottom of his chart.
Have been on HB/SO-015 on Saturday with KX1. (My first solo activation)
On 40 m there was only noise.
20 m got me two QSO. But at least 2 x S2S thanks to HB9DQM/p and HB9DST/p.
Any other calling or searching was in vain.
“W3LPL (Frank Donovan) [….] propagation “aficionado” is reporting that now and for the next 2 weeks conditions are incredible……10m open well past midnight!”
My activation of F/CR-229, Mont Puget (11.05.2024) was also very difficult. For the first half hour of my activation, I heard nothing at all on all HF bands except a station that was also activating a summit only about 70 kilometres away from me.
We first had a S2S on 20m. But his modulation was very special. Totally hummed, abnormal and difficult to understand. A couple of minutes later we also had QSOs on other HF bands and there his modulation was completely normal. I wonder whether on 20 metres, in addition to the ground wave, the sky wave with reflection on the polar regions was somehow also playing a part or whether his device had a problem on 20m. I don’t know. I afterwards heard him calling CQ again on 20m and the modulation was still just as strange as before already on 20m.
At least I heard a few other weak signals again at the end my activation and could only make two more QSO’s to the Netherlands and Germany (S2S).