The image depicts “Simple RF Indicator,” passive device for detecting radio frequency (RF) signals in coaxial cables. It’s a clever hack using basic components
QRP
The QRP section is dedicated to low‑power HF and VHF operating, with a heavy focus on simple transmitters, minimalist transceivers, and practical on‑air results. Here you’ll find classic designs like the Mighty Mite, OXO transmitter, Mosquito TRX, and modern SDR‑based rigs such as sBitx and ZBitx tuned for portable use, all built around parts that are easy to source and experiment with. Articles emphasise repeatable circuits, clean keying, stable oscillators, and output filters so that your 1–5 W signal is both efficient and pleasant to copy at the other end
27MHz AM Transmitter Circuit for hobbyists
The 27MHz frequency band has long been a favorite among electronics enthusiasts and amateur radio operators. This citizen’s band frequency offers excellent propagation characteristics and serves as an ideal starting point for understanding amplitude modulation (AM) transmission principles. Today, we’ll explore a well-designed 27MHz AM transmitter circuit that demonstrates classic RF engineering concepts while remaining accessible to hobbyists
Simple UJT Crystal Checker Circuit: Test Your Crystals Like a Pro
Stop guessing if your quartz crystals are dead or alive! Learn how to build a Simple UJT Crystal Checker circuit to test your components like a pro. This DIY guide includes a full schematic, 2N2646 UJT tips, and step-by-step instructions for quick troubleshooting.
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.
80 meter 1W QRP Transmitter with Ceramic Resonator Control
Simple 80 m CW transmitter using a 3.58 MHz ceramic resonator for frequency stability and MOSFET power stage — ideal first HF QRP build for beginners
Build Your Own Commando AM Transmitter
Build the Commando AM transmitter — a crystal-controlled three-transistor AM circuit with oscillator, buffer, and RF power stages delivering stable modulation for HF experimentation
Build Your Own 80M CW Transmitter from Scratch
Learn to build a simple 80M CW transmitter with crystal oscillator and parallel power amplifier. Complete circuit guide for amateur radio enthusiasts
Build Your Own Grenade AM Transmitter Circuit: A Complete Guide
The Grenade AM transmitter is a fascinating DIY electronics project that combines simplicity with effective radio frequency transmission.
Build Your Own 40M AM Transmitter: A Classic Radio Project
This blog post delves into the construction of a 40M AM transmitter. Perfect for hobbyists offers a fantastic hands-on experience with RF electronics.