DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
DIY VHF antenna projects and amateur radio guides for the 2-meter band and wider VHF spectrum. Explore loops, collinear verticals, sleeve dipoles, and dual-band designs with dimensions and performance tips.
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
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
Quarter-wave COCO antenna design for 2 m band: stacked λ/4 coax elements with phase-reversing joins for compact high-gain VHF performance and easy DIY construction
Here is a high performance RF amplifier using MAX2633 for the entire VHF band that can be successfully built without any special test equipment. The grounded -gate configuration is inherently stable without any neutralisation if reasonably good layout techniques are employed. The performance of the amplifier is quite good. The noise figure is below 2dB […]