G0KTN Amateur Radio - 2026 current projects and technical notes

  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...

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...

  Propagation Research Value of the WSPRnet Database The amateur radio world is a dynamic landscape, constantly evolving with new modes and technologies. Over the past few years, we've seen a massive shift towards digital modes, with FT8 quickly becoming the dominant mode. Its efficiency and ability to make contacts under challenging conditions, often with low power and perhaps compromised aerials has made it a popular option many operators. However, in our quest for quick and easy contacts, are we overlooking a powerful tool for scientific inquiry and propagation research? I'm talking about WSPR, and specifically, the immense historical database it creates. The Data Deficit When we fire up our rigs and make a contact on FT8, we're engaging in a classic two-way QSO, and the details are often logged on platforms like PSK Reporter and various DX clusters. These services are excellent for real-time awareness of band conditions. You can see your signals being heard and track wh...