DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
Welcome to Issue #008 of Radio Waves Weekly! This week: KrakenRF launched its plug-and-play antenna rotator on Crowd Supply just two days ago, two M.2-sized SDRs are open for orders, and a portable far-field antenna measurement system is heading to crowdfunding. Plus two wire antenna builds for this weekend, a $59 all-analog kit from VU2ESE, budget kits for new builders, CQ WPX SSB coming in two weeks, and three practical tools you should have bookmarked before Sporadic E season begins.
The Half Square has been quietly delivering low-angle DX gain to operators who know about it, while remaining invisible to everyone else — including curious neighbours. Shaped like the Greek letter π, it uses two quarter-wave verticals fed in phase through a half-wave horizontal section, matches directly to 50-ohm coax without a tuner, needs no radials, and can beat an Inverted-V by 4 dB toward the horizon. Here is everything you need to build one
Every vessel larger than 300 gross tons is legally required to broadcast its identity, position, speed, and heading every few seconds on VHF radio. With a $25 RTL-SDR dongle and free software, you can receive, decode, and map those live transmissions from your living room — no licence required, no nautical background needed. This guide walks you through the AIS standard, the hardware and software stack, antenna options, and how to contribute your decoded data to global ship-tracking networks.
Welcome to Issue #007 of Radio Waves Weekly! This week: 3Y0K is finally on the air from Bouvet Island — the most remote uninhabited island on Earth — and the pile-ups are epic. The Rebel DX Group is next up with a Kanton Island activation starting March 25. Plus a pocket-sized Indian SDR that does FT8 without a computer, the freshest QRP Labs kit, two wire antennas you can build this weekend, and a handful of contests and events to fill your log before spring.
On the day Israel and the United States launched their first strikes against Iran, a mysterious shortwave radio station flickered to life on 7910 kHz. It hasn’t gone silent since. Broadcasting streams of numbers in Farsi — a Cold War spy radio technique that was thought to be fading from use — the signal has now been logged from Europe to North America. Radio amateurs have given it a name: V32
It took just one night — February 16, 2026, 22:47 UTC — for a small group of Italian radio amateurs to change the digital HF landscape forever. FT2, developed by Martino Merola IU8LMC of ARI Caserta, compresses a full ham radio QSO to as little as seven seconds, running four times faster than FT8 and twice as fast as FT4. Within two weeks, it had been spotted on PSKReporter from dozens of countries, spawned two incompatible software implementations, and ignited a fierce debate about open-source ethics, automation, and the soul of amateur radio digital operating. This is the complete story of FT2 — the mode, the schism, and what comes next.
If you are running a multiband doublet or any antenna with a tuner, ladder line will outperform coax on almost every band. Here is how to build your own from scratch — four proven designs, common materials, and every practical detail from spacer drilling to routing it through the shack wall.
Welcome to Issue #006 of Radio Waves Weekly! This week: an Arduino that transmits clean SSB with 8 components, an open-hardware SDR transceiver with PureSignal TX, a garden fence turned into a stealth HF antenna, and a broadband V wire that covers every HF band without a tuner.
A simple length of wire can unlock nearly the entire HF spectrum—and that’s exactly what the multi-band doublet antenna delivers. Using low-loss ladder line and an antenna tuner, this classic balanced antenna provides efficient coverage from 6 m through 160 m without the complexity of multiple resonant dipoles. Whether installed in a backyard or deployed in the field, the doublet remains one of amateur radio’s most versatile and enduring wire antenna solutions.
In February 2026, amateur radio gained its fastest weak-signal digital mode — and immediately fractured it. FT2 promised ~4-second QSOs and contest-level throughput, but within days of its first on-air tests it split into two incompatible implementations. Here’s the full story of the “FT2 war,” why it happened, and what it means for HF operators everywhere.