On November 16th, 2020 the reported sunspot number was zero. Since then it has rocketed up to an astonishing 83 as of November 29th. The sunspot number wasn't forecast to hit that level until 2023 but, ready or not, here it comes: solar cycle 25. The starting date of a solar cycle is actually determined retroactively and a few months ago it was determined that cycle 25 really began a year ago in December 2019. For hams, though, the real beginning of a new cycle is when the solar flux starts getting high enough for the upper HF bands to open up and starts generating stronger signals than we are used to on the middle bands. I had noticed quite a few times recently that the 12m band was open, mostly to the US west coast and Asia. Last Friday, however, even 10m was open and I made my first new contacts on that band since 2015. Just for fun, I even made a series of QSOs that started on 10m and progressed through each band all the way down to 160m (I didn't have any luck on 60m, even though I was hearing a few weak European stations). A couple of days before that I had worked a guy in Washington state on 40m FT8, off the back of my beam, only running driver power (15 watts) and I got a report from him of +23dB. I was seeing him at +31!! I can see how the effectiveness of the FT8 mode may soon become somewhat degraded as more and more powerful signals are crammed into such a tiny sliver of spectrum on each band. Some expansion of the FT8 sub bands seems very likely in the coming years.
Ol' Sol has unexpectedly become quite active! |
Its not all fun and games, though. The more active the sun becomes, the more it tends to disrupt propagation for high-latitude stations like mine. The more active part of the cycle is marked with lots of minor disturbances that stir up the aurora and generally degrade propagation. Now the increased solar flux is making for stronger signals that can more easily break through the disturbed conditions. On days when the absorption is low and the flux is high (like last Friday) radio conditions here can be outstanding. There is also an increase in major disturbances like the little M-class solar flare that we saw this past weekend. I saw icons and colors on my propagation monitoring software that I haven't seen for years as the D-layer absorption spiked here and both the x-ray flux and proton flux climbed off the bottom of the scales where they've generally been sitting for the past few years. I blogged about how this tends to degrade the signals here back at the beginning of the last cycle and the details haven't changed at all. See here and here. An active sun makes for some very interesting effects up here in the polar region.
Colorful, isn't it? :( |
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