Saturday 15th May 2021: The last few days have been very good for Sporadic-E propagation with the 28 MHz band staying open for most of each day. The 15th of May started with the band being open from the previous day and finally closed for me at 22:44 UTC. I heard 685 WSPR transmissions from 94 stations during the day.
This was the first day of the 2021 season that I heard a 28 MHz WSPR Trans-Atlantic signal. I got just one decode of Vernon, VE1VDM's signal in Nova Scotia. Vernon was using a QRPLabs U3S transmitter with a 4-watt amp. His antenna was a full size Windom.
2021-05-15 11:50 VE1VDM FN85ij EI7GL IO51tu 28.126127 1 -22 0 4001
2021-05-15 11:58 EI2SBC IO63dj EI7GL IO51tu 28.126078 5 -23 -4 177
At -23dB and -26dB, the signal was really buried in the noise and at a level well below what is audible to the ear. As before, it's hard to be sure of the mode of propagation but I suspect it may have been either very short Sporadic-E or Sporadic-E back scatter.