Tom’s Technical Newsletter – Edition 2

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Tom's Technical Newsletter – Edition 2

Friday, 15 August 2025
Compiled by Tom VK5TOM
From the Editor

Welcome to Edition 2 of Tom's Technical Newsletter!
This week, we've got everything from a brewing spectrum battle and easy homebrew antenna projects, to timeless propagation tips, space history, cutting-edge single-board computers, and a shack tour to inspire your next station upgrade.

Whether you're building, operating, or just reading over a cuppa, I hope you find something here that sparks an idea for your own amateur radio adventures.
1. Amateur Radio vs AST SpaceMobile – The Spectrum Standoff

Amateur radio operators worldwide are raising concerns about AST SpaceMobile's proposal to use the 430–440 MHz (70 cm) band — long reserved for amateur use. Operators fear that large-scale commercial activity here could cause harmful interference, disrupting weak-signal work, satellites, and other activities that hams have relied on for decades.

I know this is a complex issue, but I wanted to highlight how seriously the ham community views this — and why it matters to us all in amateur radio.

Read more:
https://au.pcmag.com/wireless-carriers/112527/ham-radio-users-explain-why-theyre-worried-about-ast-spacemobiles-satellite-plans
2. Homebrew Project – Build a 6 m 2-Element Yagi

If you're looking for a simple and effective 6 m antenna, this 2-element Yagi is an excellent project. It uses a compact boom (~0.75 m), about 60 cm spacing between elements, and delivers around 6.5 dBi gain. A perfect beginner's build — low cost, easy construction, and a great way to explore 6 m DX.

Step-by-step guide:
https://q82.uk/how-to-build-a-6m-2-element-yagi
3. Sporadic-E Insights from the Air Force

This article might be from 2020, but the way it explains sporadic-E propagation is still spot-on for today's 6 m operators. It's a great refresher on how and why those sudden band openings occur.

Also, a personal note — special thanks to Mick VK5MCH for building me a brilliant 6 m flowerpot antenna. I've included a photo of it below so you can see the setup that's been helping me make the most of those fleeting openings.

Read the AFRL sporadic-E explanation:
https://www.af.mil/News/Article-Display/Article/2342059/air-force-research-laboratory-tracks-sporadic-e/

4. Remembering James Lovell – The Man Who Cheated Death in Space

James Lovell, commander of Apollo 13, passed away this week. Lovell's leadership during the near-disaster showcased ingenuity, calm under pressure, and teamwork at its finest. Hackaday's tribute is well worth a read.

Read the tribute:
https://hackaday.com/2025/08/12/remembering-james-lovell-the-man-who-cheated-death-in-space/
5. VisionFive 2 Lite – Affordable RISC-V SBC

A new entry-level RISC-V single-board computer, the VisionFive 2 Lite, has been released starting at just US $19.90. Ideal for Linux tinkering, education, and embedded projects.

Details:
https://www.cnx-software.com/2025/08/07/visionfive-2-lite-low-cost-risc-v-sbc/
6. K4USA Shack Tour – All Bands, All In

For some station-inspiration, check out this shack tour from K4USA — every band, every piece of gear, beautifully organized. Plenty of ideas here for your own station setup.

Watch on YouTube:
https://www.youtube.com/watch?v=DFB_MYKNUWE

73,
Tom VK5TOM