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Showing posts with the label 40MHz

40 MHz (8 m) TEP propagation from ZS6WAB – Part 2

  40MHz (8m) TEP propagation from ZS6WAB – Part 2 Solar drivers, event behaviour and what the data can (and cannot) prove Introduction In Part 1, the ZS6WAB 40.675 MHz CW beacon dataset demonstrated that transequatorial propagation (TEP) into Europe is: Repeatable Strongly seasonal More prominent during the stronger years of Solar Cycle 25 The next question is straightforward: What governs individual TEP openings? This article examines how the observed events relate to solar and geomagnetic conditions, while remaining grounded in what the dataset can realistically support. A note on methodology Before looking at the data, several limitations must be recognised: CW spotting is not continuous Event start/end times are approximate Mode labels are operator assigned No direct ionospheric measurements are included This means that the dataset is well suited to identifying patterns and correlations, but not sufficient on its own to establish causation. Sola...

40MHz (8m) TEP propagation from the ZS6WAB CW beacon

  40MHz (8m) TEP propagation from the ZS6WAB CW beacon Why ZS6WAB matters The ZS6WAB CW beacon is situated near Polokwane, South Africa in QRA locator KG46 and runs 30W to a 5 element yagi pointed north towards Europe on a nominal frequency of 40.675MHz. Its southern hemisphere location makes it ideally placed for studying transequatorial propagation (TEP) into Europe. More importantly, it appears to be the only consistently monitored beacon on this path. The dataset analysed here spans 16 June 2022 to 16 March 2026 and comprises 2,502 reception reports submitted via DX Cluster and the UK Beaconspot archive. TEP: a long-studied but still evolving mechanism Transequatorial propagation is not new. It has been studied continuously since the late 1940s, with the first recognised observations dating back to around 1947. Despite decades of research, TEP remains an active area of investigation, with new refinements and theoretical developments still being proposed. Modern understand...

40MHz WSPR Beacon Continues for Third Year

  40MHz WSPR Beacon Continues for Third Year - Studying 8m Band Propagation I am pleased to report that Ofcom has granted approval for a third year of operation of the 40.680 MHz WSPR beacon (plus the usual 1500 Hz offset). The beacon operates as a propagation indicator on the 8m band (40 MHz) and as a data source for anyone interested in studying propagation   at this  part of the spectrum . Reception reports from the beacon are archived in the WSPRnet database and are available for download via: wspr.rocks Spot data has been accumulating since April 2024 , providing a growing dataset for anyone interested in analysing 8m propagation trends . Why Study Propagation on the 8m Band? The 40MHz region occupies an interesting position between the traditional HF bands and the low VHF spectrum. Because of this location in the radio spectrum, signals on 40MHz often demonstrate propagation mechanisms that share characteristics of both HF and VHF . Most openings on ...

8 Meters: The Post-Peak Dip

  8 Meters: The Post-Peak Dip – Why Transatlantic F2  DX Isn’t Matching Last Year’s Benchmark (and why a WSPR Beacon might matter) 40MHz  operation has become an increasingly active area of propagation research within amateur radio. The 8m  band ( 40MHz ) sits high enough in the radio spectrum that F2  layer support is only possible during periods of high solar intensity. For UK operators, frequent direct  F2  propagation to North America serves as a benchmark indicator of robust ionospheric conditions. In autumn 2024, such transatlantic F2  paths were already frequently workable by mid-October. This year, activity has been noticeably reduced, prompting a few to ask: why the significant drop-off? The answer lies in the Sun’s subtle yet powerful progression beyond the peak of Solar Cycle 25. Solar Drivers of 40MHz  F2  Propagation The F2  region's electron density profile determines the Critical Frequency foF2  and, crucially th...

40MHz (8 m) WSPR Propagation Analysis — G0KTN to WESSEXSDR3

40MHz (8 m) WSPR Propagation Analysis — G0KTN to WESSEXSDR3 (IO81ti → IO80qr) I wanted to know the propagation mechanism involved over a 72km path to the Wessessdr3 receiver at 40MHz so I obtained the relevant data from the WSPRnet archive and requested ChatGPT to analyse the file and produce a report. Most, if not all of the content is, of course, already well known and the results are not going to shake the world of propagation science but it does demonstrate what a useful and powerful tool AI is especially when applied to your own data. 1. Introduction Between November 2024 and March 2025 I carried out a WSPR propagation study on the 8 m (40 MHz) band using the low-power beacon at G0KTN , QRA IO81ti , into a half-wave dipole approximately 20 ft (6 m) AGL . The beacon transmits continuously at 40.681 MHz with an output of 1 W . Reception was monitored via the WESSEXSDR3 web-SDR at I O80qr ( wessex.hopto.org:8070 ), a site 70–72 km distant at 250 m ASL . The SDR uses a ter...