I have a Sirio 2016 vertical 10m antenna up at home, approximately 1100ft in Mid-Wales. I will watch your spots and have a listen if the band is open - fingers crossed. No chance on 2m unfortunately Good luck!
Hi Éric, I find this dx-heat.com chart useful since you made many of us aware of it (via this reflector). But as you pointed out, it shows activity on the band so it’s only an indirect indicator of propagation conditions. So, for example, a band could be open even when there’s little or no activity shown on the chart. For that reason, I have the frequency on 20m, 15m 10m, etc of the coordinated beacons programmed into my rig for a quick check of conditions.
I don’t think 120deg - or for that matter, 90deg - is very critical. I copied the MM0FMF vertical with one radial which works very well, I tried it with two in an inverted T formation and got very little improvement, and with four got no additional benefit.
You were on Ingleborough or Whernside I think and I was on Arnside Knott (LoS, ~28km away). I was trying to chase a US station on 20m [hoping to sneak in between QRO home chasers] and you chased him - you were 599+ with me. I can’t imagine any other propagation mode other than ground wave over that short distance.