Boost your HF reception with this classic Active Antenna circuit covering 0.5 to 30 MHz. Learn how to build a high-gain, low-noise wideband antenna perfect for SDRs and shortwave receivers in space-constrained environments.
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.
Log audio Compressor Circuit for Smooth Natural Compression
Discover how to build a Logarithmic Audio Compressor circuit for smooth, natural-sounding audio. This guide features a high-performance schematic using precision op-amps and log-antilog transistors to prevent distortion while maintaining consistent signal levels for amateur radio and pro-audio projects.
Audio Clipper Circuit Using BC547 and 1N914 Diodes
Learn how to build a simple and effective Audio Clipper Circuit using BC547 transistors and 1N914 diodes. This DIY guide covers schematic details, component selection, and how to prevent overmodulation in amateur radio transmitters for clearer, peak-limited audio.
Build a Miniature FM Transmitter – DIY Electronics Project
Learn how to build a compact, high-sensitivity Miniature FM Transmitter with this DIY electronics guide. Featuring a simple transistor-based schematic and an electret microphone, this project is perfect for beginners exploring RF circuits and wireless audio.
Microphone Preamplifier with Audio Peak Limiter
The circuit shared here is a Microphone Preamplifier with Audio Peak Limiter, often used in audio recording, amateur radio, or intercom systems. It amplifies weak microphone signals and includes peak clipping diodes to prevent signal distortion from loud inputs. Looking to boost your microphone signal while keeping audio distortion in check? This two-stage transistor microphone […]
DIY 3-Transistor FM Bug Transmitter Using Piezo Mic
Build a high-sensitivity DIY 3-Transistor FM Bug Transmitter using a piezo microphone. This step-by-step guide includes a stable schematic, BC547 transistor tips, and frequency tuning advice for crystal-clear long-range audio monitoring.
How to Build a 3-Watt AM Radio Transmitter
There is something magical about hearing your own voice or music coming through a vintage tube radio from across the room—or across the neighborhood. While many low-power “flea” transmitters struggle with range, this 3-Watt AM monster brings some real “punch” to the Medium Wave band.
In this project, we’re stepping up the power. Using the classic BD139 transistor and a rock-steady crystal oscillator, we’ll build a transmitter that balances simplicity with performance. Whether you’re a Part 15 enthusiast or just want to experiment with AM modulation, this circuit is the perfect way to become your own local broadcaster. Let’s get on the air!
Build a Simple 40 Metre CW Transmitter Using 2N2222
Build a simple 40 m CW transmitter using a 2N2222 and 7 MHz crystal oscillator — a minimalist QRP design with keyed oscillator and low-pass filter for clean HF Morse transmission.
Simple FM Transmitter Using BC547 Transistors
If you’re a radio electronics enthusiast or hobbyist, building a Simple FM transmitter using readily available components like BC547 transistors can be both fun and educational. This compact circuit transmits voice signals captured via an electret microphone to a standard FM radio receiver, making it perfect for short-range audio transmission projects. Simple FM Transmitter – […]
Crystal Radio Explained – How to Build Your Own No Power Radio
Discover the magic of “no-power” radio! Step-by-step instructions on building a crystal set that runs entirely on the energy of the radio waves it receives.

