DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
Explore a detailed collection of antenna projects and DIY designs at vu3dxr.in. This tag features practical builds, tuning guides, and performance tests for various amateur radio antennas. From wire dipoles to specialized SDR antennas, discover step-by-step instructions to help you construct and optimize effective aerials for your radio station.
Master the construction of the high-performance Sleeve Dipole antenna using only coaxial cable. This technical deep-dive explains how the “sleeve” acts as a decoupling balun, providing a clean radiation pattern and low SWR for VHF/UHF and HF applications without external chokes
Learn how to build a simple high-gain collinear antenna using coaxial cable for VHF/UHF amateur radio. Low-cost DIY design with improved omnidirectional coverage and better range than a standard vertical
Discover the RW4HFN balcony antenna design for the 20-meter amateur radio band—ideal for limited spaces. Includes schematic, dimensions, and inductance values
The RA9SUS simple loop is a compact HF antenna covering 14–30 MHz using a 4.7 m rectangular loop and variable capacitor tuning. Ideal for balconies and small spaces, it enables efficient multiband operation without large wire antennas or ground systems
Full-size Delta Loops for the 40-meter band normally require around 42 meters of wire—often impossible for operators with limited space. To overcome this challenge, Andy (2E1TAP) documented his attempt at constructing a space-efficient, shortened 40-meter Delta Loop.
Compact 4 m shortened vertical antenna for the 80 m band using a 64 µH loading coil and LC base matching network. UR0GT design enables efficient 3.65 MHz operation in small spaces with full-size radial system for strong HF performance.
Compact dual-band RW4HFN antenna covering 145 MHz (2 m) and 430 MHz (70 cm) with a center-fed element and integrated matching section. Single-feed 50 Ω coax design provides versatile VHF/UHF operation for base, portable, and repeater use.
The broadband butterfly (bi-square) antenna uses two connected square loops to deliver stable 50–75 Ω impedance, low noise, and several dB gain over a dipole across VHF/UHF bands. Simple bidirectional design requires no tuning and scales easily for 144 MHz and 430 MHz operation
The dual-band 144/430 MHz Square Loop Antenna is one of the most efficient and compact VHF/UHF antennas that amateur radio operators can build at home. Designed to cover both the 2-meter and 70-centimeter bands, this antenna offers excellent gain, low noise reception, and impressive SWR when constructed correctly.
Ditch the lossy traps and discover the Morgain Antenna—a clever, compact dual-band dipole for 40m and 80m. Operating at just 20 meters long, this wire-only design uses folded elements to achieve resonance without bulky coils. The ultimate space-saving solution for your HF station