DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
Unlock elite DX performance with the Switchable Delta Loop. This detailed guide covers everything from the 141-foot 40m foundation to the ingenious 18-inch tuning tails that enable seamless 30m operation. Perfect for hams seeking a low-angle radiator with a manageable footprint
The Doublet Dipole remains a favorite for hams seeking multiband efficiency without complex hardware. By utilizing balanced feed lines and a 4:1 balun, this antenna design overcomes the limitations of traditional coax-fed dipoles. Our guide breaks down the essential formulas and provides a detailed dimension table for the 80m, 40m, 20m, and 15m amateur radio bands for your next project.
Welcome to Issue #010 of Radio Waves Weekly! A landmark tenth issue, and the news matches the milestone. KP5/NP3VI has just gone QRT from Desecheo Island after 104,000 QSOs on solar power alone — a first in DXpedition history. TX9W heads to the Marquesas in three weeks. WSJT-X Improved 3.1.0 brings FT2 into the open-source world. iDigi 2.2.2 puts eight digital modes into one native macOS app. SP DX Contest opens Saturday, POTA Spring Weekend is April 18-19, and two unusual wire antennas from vu3dxr.in await your weekend.
Build a triband delta loop antenna for 80M, 40M & 30M. This trapped delta loop antenna guide covers traps, matching section & construction details
Unlock dual-band performance with the Open Stub J-Pole. This comprehensive guide details how to construct a 2m/70cm antenna using a single feedline. By following precise dimensions for the 146 cm, 48.9 cm, and 15.9 cm rods, hams can build a durable, high-gain vertical dipole perfect for home or field use.
This guide explains DRM basics, SDR devices, and a complete working setup using HDSDR and DREAM. Build a DRM receiver step by step while learning how digital radio works on SDR platforms.
Discover the secrets of the Beverage antenna. We explain how to match 450-ohm impedance to your coax and how to build a termination load that survives accidental 100W transmissions.
Tired of “RF in the shack”? This detailed guide walks you through building a DIY RF Current Sniffer using LED and Meter indicators to troubleshoot your coax cables.
This 6 meter antenna gives you strong, stable performance with a simple build. It covers a wide range, holds a good match, and behaves like a compact directional array.
Struggling with limited space or high local noise? The Magnetic Loop antenna is the ultimate “stealth” solution for hams. We dive deep into the PA0WIT design, featuring a 1/5 ratio Faraday loop for a perfect 1.1 SWR and peak performance from 7MHz to 18MHz.