Opening from Hawaii to Europe on 28 MHz - March 2024

Over the last few weeks, I have been listening on the WSPR frequency of 28.1246 MHz and feeding the decoded WSPR signals to the WSPRnet website. As we're near the peak of the sunspot cycle, I was  hearing stations all over the world on the 10m band. I know when I see east-west paths open to the west coast of the USA and to Japan then conditions must be good.

One unusual signal though was the club station KH6EJ in Hawaii. The power output is just 0.2 watts into a MFJ 1982-LP antenna and it transmits on 80m, 40m, 30m, 20m, 17m, 15m, 12m & 10m. The 28MHz transmissions are at 18, 38 & 58 minutes past the hour. 

The received signals were in the range of -23dB to -29dB which means they were buried in the noise. These are the four decodes...

 local   y-m-d txCall txGrid rxCall rxGrid MHz W SNR drift km
2024-03-20 18:58 KH6EJ BK29 EI7GL IO51tu 28.126175 0.2 -23 0 11449
2024-03-20 18:38 KH6EJ BK29 EI7GL IO51tu 28.12617     0.2 -29 -1 11449
2024-03-14 18:38 KH6EJ BK29 EI7GL IO51tu 28.12614         0.2 -25 0 11449
2024-03-11 18:58 KH6EJ BK29 EI7GL IO51tu 28.126062 0.2 -23 0 11449

Why is it unusual?

1) I was the only station in Europe to decode the KH6EJ 10m WSPR signal over a 4-week period. Obviously my location in the north-west of Europe helps but I'm only using a simple vertical half-wave antenna for receive. Why didn't other stations in Europe decode the signal?

2) The short time window. I got just four decodes over the space of three days and they are all in the 18:38 to 18:58 UTC time window. This is close to the sunset times for my location.

3) The northerly path. The auroral zone in the Arctic can and does distort signals. If the signals are on  SSB or CW then they can sound a bit rough but for digital signals like WSPR or FT8, it can often mean that the signals are not decoded at all. 

In conclusion... I've worked Hawaii on 28 MHz a long time ago but if I was looking for it now as a new country on 10m then I'd be checking the band at sunset in March.