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CW Reverse Beacon Observations Through the Peak of Solar Cycle 25

  CW Reverse Beacon Observations Through the Peak of Solar Cycle 25 Are amateur measurements still relevant in the digital age? Between 27 August 2024 and 22 December 2025 , my Reverse Beacon Network (RBN) node in IO81TI recorded just over five million CW spots across all the HF amateur bands from 40m (7 MHz) to 10m (28 MHz) . This period conveniently spans the run-up to, and passage through, the widely recognised peak of Solar Cycle 25 , offering a valuable opportunity to compare real-world amateur observations with official solar and ionospheric indicators. The receiving system - a Wellbrook ALA1530LN 1m magnetic loop , mounted approximately 2m agl  in a suburban back garden - is modest by any standard. That, however, is precisely the point: the dataset reflects what many amateurs might reasonably experience, rather than idealised conditions. The question explored here is simple: does this kind of amateur data meaningfully correlate with official findings, and is CW s...

CQWW CW from a Back Garden: What a Wellbrook Loop Can Really Hear

  CQWW CW from a Back Garden: What a Wellbrook Loop Can Really Hear A technical reflection on 48 hours of contest-weekend propagation from IO81ti Every year, CQWW CW gives HF radio a proper stress test, with stations worldwide lighting up the bands with thousands of signals. For those that enjoy the propagation and technical side of the hobby, it’s also one of the best opportunities to observe how the ionosphere behaves under heavy and continuous loading. This year (2025) I decided to treat the contest as a propagation experiment. My Reverse Beacon Network (RBN) node, which normally runs continuously on all HF bands, was pointed at the six HF contest bands for the entire 48-hour period: 160, 80, 40, 20, 15 and 10. The receive antenna was not a tower-mounted Yagi or a phased Beverage farm… but a Wellbrook 1530LN magnetic loop mounted about 2m above ground in a typical UK suburban back garden (QRA IO81ti). The question was simple: what can a modest receive system really hear du...

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...

A Year on Ten – What 100 Milliwatts Can Do

  A Year on Ten – What 100 Milliwatts Can Do: An Experimental Analysis Between August 2024 and July 2025, I ran a WSPR beacon continuously on the 10m band (28 MHz). The operational period coincided with the peak and plateau of Solar Cycle 25. The transmitter, Zachtek multi band, with the output suitably attenuated ran 100mW to a CIRO Mazzoni Stealth Loop mounted about 7 ft (2.1m) AGL on the flat roof of a suburban garage in southern England. The combination of an extremely compact antenna and QRPp power was designed to test the limits of weak-signal digital modes in restrictive environments. The CIRO Stealth Loop — A Compact Magnetic Radiator Although marketed as a “loop antenna,” the Ciro Mazzoni Stealth Loop is not a conventional circular magnetic loop. It is actually a flattened, rectangular radiator fabricated from TIG-welded aluminium alloy. In electrical terms, it behaves as a compact magnetic radiator. The design includes a gamma-match feed, which is short-circuited to t...