Build a high gain bi-square antenna for higher HF bands. Get 4dB gain over dipole on 10 meters with detailed calculations, matching solutions, operation tips
DIY
“DIY” on DXR Electronics Bits is where practical ham radio projects come to life. Here you’ll find buildable circuits, antennas, receivers, preamps, audio tools, and experimental rigs designed for real‑world shack and field use. From compact HF antennas for small spaces to regenerative receivers, QRP transmitters, and uBITX add‑ons, each article focuses on parts you can actually source and solder on the bench.
DIY HF Linear Push-Pull Amplifier with IRF510 MOSFETs
Learn how to build a high-performance HF Linear Push-Pull Power Amplifier using affordable IRF510 MOSFETs. This guide includes a full schematic, bias adjustment tips, and transformer winding details for 10-40W output across the HF bands.
DIY 80m Magnetic Loop Antenna: A Compact Solution for Low Bands
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
W3DZZ Multi-Band Antenna 80m-10m Trapped Dipole
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
94-Foot Multi Band Doublet Antenna – Simple All-Band HF Wire antenna
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!
A Compact 4-Meter Vertical Antenna for the 80-Meter Band
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
Extended Lazy-H Antenna: A Classic Multiband Wire Design from QST
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.
Half Loop Antenna for 80, 40, 20, and 15 Meter Ham Radio Bands
Can’t fit a full-sized 80-meter dipole in your backyard? Or maybe you’re tired of the high noise floor of a vertical? It’s time to look at the Half-Loop. This “open-loop” design provides a fantastic balance between the quiet reception of a loop and the simplicity of a wire antenna.
In this project, we explore a multiband Half-Loop configuration that covers everything from 80 meters down to 15 meters. We’ll discuss the radiation pattern, the importance of a good ground or counterpoise, and how to use a simple tuner to jump between bands. If you’re looking for a “stealthy” antenna that punches above its weight on the low bands, this build is for you. Let’s get that wire in the air!
Build a High-Sensitivity Regenerative Receiver with 2N7000 MOSFET
The 2N7000 regenerative receiver is a classic single-transistor radio that combines simplicity with surprisingly high sensitivity. By using controlled positive feedback, the circuit operates just below oscillation, dramatically increasing gain and selectivity.
Full Wave Loop Antenna for VHF UHF FM Radio Bands
Learn how to build a high-performance Full-Wave Loop Antenna for VHF and UHF FM radio bands. This DIY guide covers dimensions, polarization, and impedance matching for clear local communication and FM broadcast reception.