DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
Weather Facsimile—commonly known as WEFAX, HF-FAX, or Radiofax—is easily one of the most rewarding niches in the shortwave hobby. There is a certain “magic” in tuning your receiver to a scheduled frequency and watching a high-resolution synoptic chart or satellite image slowly materialize on your screen, line by line, over several minutes.
DIY 80 m magnetic loop antenna: 1.5 m copper tubing loop with gamma-style feed and air-variable capacitor, delivering low-noise 3.5 MHz HF performance in small areas
sBitx v5.301 update refines the v5.3 platform with FT8/FT4 stability fixes, UI polish, improved logging/UDP integration, and CW decoding tweaks — enhancing reliability of the Linux SDR transceiver
Master the 80m–10m bands with the classic W3DZZ trapped dipole. This guide explores the technical design, trap construction, and real-world SWR performance of this legendary multi-band antenna. Perfect for hams seeking a compact, high-performance HF solution without a complex tuner
If you could only ever hang one wire in your backyard for the rest of your life, the 94-foot Doublet would likely be it. Often called the “all-bander’s dream,” this specific length is a classic in the Amateur Radio world for a reason: it’s short enough to fit in most yards, yet long enough to be highly efficient on the 80-meter band.
Unlike a standard dipole that’s stuck on one frequency, the Doublet uses balanced ladder line to turn your entire feed system into part of the antenna. In this guide, we’ll look at why the 94-foot length is the “sweet spot” for multiband performance and how to properly interface it with your tuner. Forget complex traps and multiple dipoles—one wire can truly do it all. Let’s get that ladder line hanging!
Upgrade your Mini Radio Pocket SI4735 experience! The new firmware adds EiBi transmitter data and an eco-friendly power-saving mode for longer listening sessions.
sBitx v5.3 software update brings a touch-optimized UI, advanced FT8/FT4 automation, xOTA logging, CW decoding upgrades, and SWR protection — enhancing the Linux SDR transceiver platform.
Build a compact 4-meter vertical antenna for the 80-meter band. This DIY guide features a high-efficiency loading coil design and a top-hat capacity spoke system to make 80m operation possible in small yards and restricted spaces
This article will give you a complete understanding of NVIS propagation. With the level of technical expertise and detail found in this article, this guide is intended for the amateur radio operator who wants to go beyond the theory and learn the details of NVIS antenna design and operations.
The Extended Lazy-H antenna is one of amateur radio’s classic wire antenna designs, combining simplicity with reliable multiband performance. First published in the October 1955 issue of QST magazine, this antenna was intended to provide efficient HF operation using balanced construction and open-wire feed line.