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Showing posts from November, 2025

Is the 4m Band Always Open? - Part 2

  Is the 4m Band Always Open? - Part 2 A Data-Driven Look Using the GB3MBD Propagation Beacon The previous article in this series covered an analysis of reception reports of the GB3MBD beacon from my perspective, ie the spots reported just by me. This follow up looks at all spots from everyone reporting reception of the beacon during the period February 2024 to November 2025. During this period there were 829 reports from 495 days reported to the Beaconspot.UK database from stations across the UK, EI and EU. The results show that 4m is far more active, and more often open than most  realise. 1. Where the Data Comes From (and why it matters) The entire analysis is based on the Beaconspot.uk archive maintained by the UK Microwave Group . This isn’t an automated monitoring system, it collects voluntary spots that are :  Posted to the Cluster system by stations who hear or decode a beacon Or uploaded directly to the Beaconspot.uk site As a result: If no o...

Is the 4m Band Always Open? - a long term look using the GB3MBD propagation beacon

  Is the 4m Band Always Open? A Long-Term Look Using the GB3MBD Propagation Beacon The 70 MHz band has long suffered from a reputation in the UK as a “sometimes band”: occasionally brilliant during Sporadic-E season, but usually considered quiet or even dead outside local FM coverage. But is that actually true? How often is the band really open for weak-signal work? Between February 2024 and November 2025 I monitored the GB3MBD 4m FT8 propagation beacon almost continuously 24/7 and recorded the digital reception reports in the Beaconspot.UK database. Some days many spots were received but only a sample (max of 2 per day) were actually recorded in the database. The beacon transmits FT8 and CW on 70.050 MHz with around 9 W ERP , from a horizontal  halo antenna 20m AGL in IO92ra. The receiving station (G0KTN) is in IO81ti, 147 km away, using: An RSPduo SDR SparkSDR decoding software An “active” 5m delta loop with a Bonito Megaloop amplifier with the l oop apex ...

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...