G0KTN Amateur Radio - 2026 current projects and technical notes

  Why 15 Metres Becomes the Evening Surprise Band at Solar Maximum Most HF users will recognise this. You’ve come down from 10 metres hoping that 12 metres is still open, its not, so move on down to 15m fully expecting it to be fading too. And yet, it’s still there. Signals are not huge but they are workable and DX is still appearing. The band feels alive when, by instinct, it shouldn’t be. This is not imagination, selective memory, or wishful thinking. Near solar maximum, 15 metres often becomes an evening surprise band , lingering after higher bands have already failed. Using CW Reverse Beacon data during the peak of Solar Cycle 25, this article looks at why that happens and why it happens so reliably. Where 15m sits in the HF hierarchy To understand 15 metres behaviour, it helps to place it correctly in the HF spectrum. At solar maximum: 10m and 12m operate close to the MUF 20m operates well below it 15m sits in between That intermediate position is crucia...

  Do Higher HF Bands Stay Open Later at Solar Maximum? What “later openings” really mean - and what the data actually shows It is sometimes said that during solar maximum the higher HF bands “stay open later”. Some will nod in agreement, recalling evenings when 15 metres lingered unexpectedly, or when 12 metres produced signals well past the time it normally fades. But what does “stay open later” actually mean? Later than average? Later in the season? Later compared with solar minimum? And is this a consistent effect, or simply a memorable one? Using CW Reverse Beacon spot data covering late August 2024 to December 2025 (the peak and early decline of Solar Cycle 25), this article takes a look at how higher HF bands behave toward the end of the day at solar maximum, and separates genuine effects from selective memory. What operators usually mean by “open later” In everyday jargon, “open later” tends to describe one or more of the following: Signals still present after l...

  The Early Decline of Solar Cycle 25 What changes first and why amateurs often notice it before the models do Solar cycles do not end with a bang. They fade. After the excitement of solar maximum - lively higher HF bands, frequent openings, and a sense that “everything is possible” the decline phase begins quietly. There is no clear date when the cycle turns. Instead, small changes creep in, often noticed first by operators who spend time listening rather than watching indices. Using CW Reverse Beacon spot data covering late August 2024 through December 2025, this article looks at how the early decline of Solar Cycle 25 reveals itself on the HF bands , which changes appear first, and why amateur observations frequently detect them before formal models or forecasts catch up. Decline is not the opposite of ascent It is tempting to think of the solar cycle as symmetrical: what improved on the way up should simply reverse on the way down. In reality, the decline phase behaves...