DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
The Antenna category collects all of our HF, VHF, and UHF antenna designs in one place — from compact balcony loops to multiband wire antennas and portable verticals. You’ll find step‑by‑step builds for 80 m to 70 cm, including delta loops, trapped dipoles, doublets, magnetic loops, collinears, J‑poles, Moxons, and more, each with practical dimensions and matching options that actually work on the air.
Many designs are optimised for small plots, apartments, and portable operation, with notes on noise behaviour, radiation patterns, SWR results, and tuning tricks. Whether you are chasing DX on 40 m, experimenting on 6 m “magic band,” or improving repeater coverage on 2 m and 70 cm, this section helps you choose and build the right antenna for your station
The double bazooka antenna, often described as a coaxial dipole, is a time-tested antenna design widely used by amateur radio operators. Its popularity comes from a combination of simple construction, predictable impedance behavior, and noticeably lower received noise compared to thin wire dipoles.
If you’re hunting for a high-performance antenna that doesn’t look like a metallic porcupine, the Hourglass Loop (popularized by KE4ERO) is a fantastic weekend project. It is essentially two delta loops stacked and fed in-phase, resulting in a bidirectional pattern with about 5 dB of gain over a standard dipole.
DIY 300 Ω twin-lead J-pole antenna for the 2 m band offering efficient VHF performance, easy coax feed, and portable installation without radials
Build a simple twin-lead J-pole antenna for VHF/UHF using 300-ohm ribbon cable. This end-fed half-wave vertical with quarter-wave matching stub delivers omnidirectional coverage, low noise, and reliable FM/repeater performance without ground radials
Compact multiband HF dipole covering 10–80 m using symmetrical loading coils and coax matching section. Single-wire antenna for small spaces enabling 80, 40, 20, 15, 11, and 10 m operation with an antenna tuner.
High-gain 435 MHz UHF collinear antenna using three 5/8-wave vertical sections with inductive phasing. Provides ~6 dB omnidirectional gain and low-angle radiation for repeater, base, and long-range 70 cm band operation.
Build a VHF Super J-Pole (collinear J-pole) antenna by stacking two half-wave elements with a phasing stub for ~3 dB gain over a standard J-pole. Omnidirectional, low-angle radiation vertical ideal for 2 m repeaters and long-range VHF communication
Operating on 80m, 40m, and 20m from a small backyard is no longer a challenge. Learn how to build a compact, loaded multiband HF dipole that uses precision-placed coils instead of traps. This high-efficiency design offers resonant performance on three major bands using a single 1:1 balun
Build a 4:1 un-un impedance transformer to match end-fed wire antennas to 50 Ω coax. Ideal for long-wire, vertical, and off-center-fed antennas, improving SWR and RF transfer in multiband HF installations.
This article explains the construction, operation, and real-world usage of a 9:1 impedance transformer (UN-UN) for long wire and random wire antennas, making it ideal for SWL listeners and amateur radio operators.