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How to build a complete Single-Sideband amateur radio transceiver from scratch. Article published on hackaday dot com includes an introduction to radio architectures, ssb receivers and tramsitter

Key details about the superhet or superheterodyne radio reeiver: basic overview; how it works; applications; design notes, all you need to know.

Since 2011, crkits offer radio kits that you cannot find on eBay or AliExpress. Includes HT-1A 20/40m Dual Band CW Transceiver Kit, D4D DSB Transceiver Kit for Digital Mode, R3500D ARDF Receiver, CW Transceiver Kit

This FM wireless mike can transmit voice signals to any FM Radio receiver 100 meters away.

Gimme Five reloaded, a compact 5 band QRP SSB transceiver in SMD technology. This unit covers 5 bands within the amateur radio spectrum (3.5, 7, 14, 21 and 28 MHz). Receiver is a single conversion unit with an interfrequency of 9 MHz. Transmitter uses 5 stages and has got a power level of 10 watts PEP output.

VHF-UHF receiver covers from 25 to 800 and 900 to 2000 MHz in the following modes: AM, AM-W, FM, FM-W, FM-N, USB and LSB

Manufacturer of software definded radio receivers, antenna switches, preselectors, antenna splitters based in Italy and USA

Crystal receivers are radio receivers that work without a power supply or batteries. Gallery of some crystal radio projects

Stand Alone Software Defined Radio, direct sampling receiver from 30 kHz to 1700.00MHz continuous frequency range, LAN interface for remote access

The build was an experiment to see if a tube receiver could be stable enough to receive digital shortwave radio broadcasts. The tube acts as both an oscillator and mixer, so the receiver is a type of direct conversion receiver.

A very small receiver converter that can be plugged to the backside of the battery powered portable transceiver FT817 from Yaesu. A high performance receiver for 2.3GHz amateur radio signal

List of global weather fax (HF fax) stations, including their locations, call signs, and frequencies. Click on any station's call sign to view its weatherfax broadcast schedule. This site provides various radiofax receiver manuals in PDF format, on the Receivers page.

Super Simple APRS Position Reporter. This project idea has been in response to the more hardware heavy Raspberry Pi projects that involve extra TNC hardware, additional sound cards, and custom cabling. This APRS position reporter is done using a Raspberry Pi B+, USB GPS receiver, Baofeng UV-5R, and a mono 3.5mm audio cable between the Pi and HT.

Tuning into the airwaves for new and interesting transmissions has fascinated enthusiasts since the very earliest days of radio. As a result of advances in computer and radio technology, the equipment packed radio rooms of the past are now replaced by scanning receivers sometimes just the size of a mobile phone. What can radio receivers/scanners pick up? What types of radio receivers/scanners are there? What can and cannot be monitored legally? Best practice when using a radio receiver/scanner

This blog article introduces an updated repeater controller project utilizing the Arduino UNO. It includes a CW identifier, and the ID message can be customized using hex codes. The author offers a Windows command line program for easier message coding and provides a link for download. The controller features three adjustable timers for IDer, Timer-out, and Squelch-tail. The article also mentions the use of an audio switch to control audio levels between the receiver and transmitter. Detailed instructions and code files are available on the author's website for both version 1 and version 2 of the Arduino repeater controller. The project aims to enhance repeater functionality and audio management in ham radio operations.

Listen to online WebSDR located in Andorra Europe. Four receivers on 60m, 20m, 40m, and 80m, connected to a dipole antenna direction East/West

A page dedicated tho the IC-756PROIII transceiver. This radio, discontinued, incorporates many of the features that made its predecessors so successful. However, the integration of the latest technology employed in the IC-7800 such as receiver technology, +30dBm class IP3, miniscope makes this new rig the very pinnacle of the IC-756PRO series.

Digirig is an open-source integrated digital modes interface for amateur radio. As a differentiating feature, Digirig only requires a single USB connection to the computer with all the digital goodness packed in a single small enclosure. The internals include a USB hub, audio codec, a fully featured serial CAT (Computer Aided Transceiver) interface, and potentially other modules such as GPS receiver for time synchronization.

This project revisits a minimalist software-defined radio (SDR) receiver built using a Raspberry Pi Pico, now optimized for simplicity and affordability. Designed for breadboard assembly with through-hole components, the receiver covers 0–30MHz, supporting CW, SSB, AM, and FM modes with an OLED display and spectrum scope. Key improvements include enhanced frequency accuracy, reduced op-amp saturation, and lower-cost components. Powered by three AAA batteries, it delivers standalone operation for global signal reception. Ideal for hobbyists, the design fosters experimentation and is documented with firmware and schematics available online.

Since 2012, the RTL-SDR is the simple and cheap way to give Software-Defined Radio a try. For about 25 euro you get a receiver covering much of the VHF and UHF range, and by either adding an upconverter, or using the direct sampling option, also the HF bands. They are so cheap because they are mass-produced as DVB-T receivers.

A guest review of the FLEX-6400M DSP HF Trasnceiver considering just the receiver part of this radio.

Amateur radio SDR Receiver and Transceiver manufacturer , makers of the Silphase R1 an innovative HF receiver with high performance real-time spectrum scope.

Explaining ARRL Technical Reviews of Radios a brief tutorial on radio testing. The ARRL Lab tests radio equipment according to standardized test procedures, using calibrated professional test equipment. Info on transmitter and receiver tests

A 70cm / 432 MHz Transverter Project transverter circuit is an electronic device that converts a radio signal from the 2 meter to the 70 centimeter band and vice versa, allowing a single transmitter/receiver to be used for both bands. It consists of an IF stage, local oscillator, frequency multiplier, and amplifier. The circuit must be designed for minimal signal loss, noise and intermodulation distortion.

A simple superheterodyne receiver (3.5–30 MHz) for amateur radio achieves stable SSB-CW reception using modern BJTs, an AD831 mixer, a 6-pole quartz filter, and Seiler oscillators. Designed with high IF (4.5 MHz), compact AM-FM variable capacitors, and modular resonant circuits, it ensures selectivity, image rejection, and stable tuning. Built in a copper-lined wooden case, it features practical assembly techniques but lacks advanced features like AGC or S-meter. Effective on basic antennas, it achieves global reception.

Learn how to build a QRP digital transceiver with Arduino, based on a project by Burkhard Kainka. This article covers the development process, including the source code, modifications made, and the addition of an OLED display for a more professional look. Discover the inner workings of the transceiver, from the receiver to the oscillator, and how components like the CD2003 are utilized. Explore the schematic design, the use of a PLL module Si5351A controlled by Arduino nano, and more. Ideal for hams looking to create their own digital transceiver for amateur radio operations.

The page presents JRX, a virtual radio receiver interface written in Java that can connect to about 200 ham radio transceivers and receivers using the Hamlib library. It offers features like 200 read/write memories, a programmable scanner, and spectrum scope, making it easier to use than traditional radios. The article explains the benefits of virtualizing a radio with controls and highlights the advantages of using JRX, especially for radios requiring computer control. Author P. Lutus provides insights on the development of JRX and its improvements over previous virtual radio projects.

This article explores the revival of the classic 3 Transistor Short Wave Radio kit originally offered by Radio Shack in the late 1960s. Updated with modern silicon transistors and components, the design retains its educational charm while enhancing performance. Detailed assembly instructions and illustrations are provided to facilitate replication. The project not only pays homage to nostalgic electronics but also serves as a practical introduction to radio theory, including modulation techniques and receiver types, fostering a hands-on learning experience for enthusiasts.

Quisk is a Software Defined Radio (SDR) and is the software that controls my receiver and transmitter. Quisk can control the HiQSDR, Hermes-Lite hardware, SoftRock hardware, SDR-IQ by RfSpace

A 3.5–24 MHz regenerative receiver for amateur bands was recently constructed, inspired by a 1934 design. The project was both challenging and rewarding, requiring precise tuning and high-quality components. The receiver successfully captured QSOs from across the globe, such as New Zealand communicating with Panama. The simplicity of the design and the satisfaction of building a functional, compact wooden box with handmade resonant circuits were highlights. This project demonstrates a meaningful way to reconnect with the roots of amateur radio.

This page by Lajos Hoss, HA8HL, provides a detailed guide on how to build a simple direct receiver using FT8QRP CAT control support. The author shares his experience in making QSOs with FT8, WSPR, and JT65 modes during the Covid-19 lockdown. Modifications to the VFO, transmitter design using BD329 transistor Class A amplifier, and the challenges faced in achieving clean output signals within legal limits. This project is interesting for those hams that are interested in experimenting with DIY transmitter projects and understanding CAT control support for various amateur radio modes.

This guide explores the captivating hobby of shortwave listening (SWL), offering insights for beginners and enthusiasts alike. It covers key shortwave broadcast bands, essential tools like antennas and receivers, and practical tips to enhance listening experiences. Recommendations include budget-friendly SDR receivers, traditional radios like the TECSUN PL-680, and antennas suited for various environments. Additional resources, such as the World Radio & TV Handbook and online tools like Short-Wave.Info, are highlighted to help identify signals and maximize the enjoyment of SWL.

Radio Frequency Interference (RFI) has always been a source of concern for the Radio Amateur. Until the recent introduction of complex circuitry in the home, our communications gear has been the main source of potential RFI. In this computerized age of ours, increasingly complex and sensitive receivers are being barraged by these and other sources of RFI.

This article explores the nuanced design challenges of Band Pass Filters (BPF) in radio receivers, balancing low insertion loss, high stop band rejection, and narrow bandwidth. The focus is on the "Series-Trap, Shunt-C" topology, resonator count impact, and meticulous layout design for superior stop band performance across various frequency bands

The recognition of telegraphy masked by noise at 40 and 80 signs/min telegraphy speed was studied in 10 normal-hearing subjects at different sound pressure levels (25-85 dB SPL in steps of 5 dB) as well as at different test frequencies (2000, 1000, 800, 630, 500 and 250 Hz). The ability to recognize the signs varied with varying SPL. Recognition for most of the subjects was best at an SPL close to 70 dB. All subjects improved their recognition as the frequency was lowered to 500 Hz, some even at 250 Hz. These facts should be taken into consideration when training telegraphy operators as well as in the construction of radio receivers to permit listening at low frequencies. Furthermore, the critical ratio was calculated at the different test frequencies.

The article discusses the use of SDR# (SDR SHARP) software for SDR receivers, highlighting its Band Plan feature that visually represents RF spectrum allocations. The author modified SDR# to display detailed IARU HF band plans, creating three XML files for different IARU regions. These files include various operational modes and specific frequency allocations. Despite potential errors, the modifications aim to enhance the usability of SDR# for ham radio operators. The article includes references and download links for the XML files and IARU band plans.

This loop antenna is intended to be connected as an antenna for receivers that do not have a built-in antenna such as an HF set or an old tube radio. This square barrel is wound on a wooden frame. It consists of two windings that are galvanically isolated from each other, a main and a coupling winding. The diameter is about 40 cm.

Kanga Products offers a diverse range of kits and pre-built items for amateur radio operators, including Morse tutors, keys, antenna tuners, and dummy loads. Their products cater to both beginners and advanced users, with options for practice oscillators, receivers, and various electronic components. The company provides detailed instructions and supports DIY projects, making it a go-to for hobbyists seeking practical and educational tools.

The RTL-SDR tuner dongle is a popular tool for amateur radio enthusiasts, transforming a $10 device into a wide-band software-defined radio. This guide outlines using the RTL-SDR as a full-band pan-adapter for conventional receivers, focusing on hardware setup and software integration with HDSDR. Future sections will address RTL-SDR performance compared to native receivers, enhancing digital mode operations with virtual serial ports and audio cables.

This document outlines various miniature projects undertaken by Mike Markowski to enhance his skills in GNU Radio. Key projects include an FM stereo receiver and an AM radio receiver, featuring advanced functionalities like pilot tone recovery and RDS integration. Additional experiments involve generating Gaussian noise, chirp signals, and Morse code decoding, emphasizing hands-on learning and customization in GNU Radio. The author encourages feedback and shares flow graphs and Python code for each project, aiming to foster community engagement and knowledge sharing.

Spectrogram, a PC-based audio frequency spectrum analyzer available from Visualization Software, aids ham radio enthusiasts in aligning receivers like Elecraft K2. Versions are downloadable, with an intuitive interface and customizable parameters. Tutorials by experts like Tom Hammond and John Grebenkemper offer additional guidance.

This page provides a detailed guide on how to receive WWVB 60 KHz time signals using the Everset ES100 module with an Arduino Due microcontroller. It explains the background of time standards and the significance of WWV radio stations in maintaining these standards. The content is useful for ham radio operators interested in time synchronization, scientific research, navigation, and radio communications. The article is written by Keith Greiner, who shares his project inspired by his passion for the subject. For more projects by the author, visit the provided links.

The F6AOJ RX splitter project was created to split the antenna signal from an LZ1AQ receive loop to multiple receivers, such as radios or SDRs. The design is simple to build and effective. The splitter, mounted on the back of the LZ1AQ control board, provides two outputs—one for an Afedri SDR and another for a K3 transceiver. Measurements show a damping of -3.01 dB at 1 MHz and -3.10 dB at 30 MHz, with a low SWR (max 1.07 at 30 MHz and 1.4 at 60 MHz).

This page presents the Arduino radio receiver project created by EasyEDA in 2024. It includes design drawings, BOM, and project details. The content is aimed at hams interested in building their own radio receiver using Arduino technology. The project is shared under a CC BY-ND 4.0 license, allowing others to replicate and modify it. The page also includes comments from project members, making it a useful resource for hams looking to explore radio receiver construction.

This project details the development of a modular direct conversion (DC) receiver designed for experimental flexibility in amateur radio and HF signal listening. The mainframe integrates a diplexer, DBM, and AF amplifier, supporting interchangeable local oscillator and antenna filtering setups. A tunable passive HF preselector complements QRP Labs bandpass filters for enhanced signal reception. Utilizing a NanoVNA for precise tuning, the receiver achieves improved signal-to-noise ratios across amateur and non-amateur bands, making it a versatile platform for further RF experimentation.

This page discusses a simple receiver protection device designed by Matt Roberts for hams. The article details the purpose, construction, and usage of the RF clipper, providing useful information for ham radio operators looking to protect their equipment from RF overload. The content is practical and informative, offering a solution to a common issue faced by hams.

Learn how to build a simple tuned loop antenna for the AM broadcast band to improve the performance of your radio receiver. Discover how to construct a loop antenna with readily available materials, such as balsa and basswood, without the need for specialized woodworking tools. Follow step-by-step instructions to create a portable loop antenna that offers good gain and directivity, ideal for pulling in weak stations. Enhance your Ultralight DX'ing experience and explore the world of FSL antennas through this practical DIY project.

Direct conversion receivers (DCR) are gaining renewed interest due to advancements in semiconductor technologies and their suitability for integration in compact, low-cost, multi-standard applications. Unlike traditional superheterodyne receivers, DCR eliminates image frequencies and bulky off-chip filters but introduces challenges like DC offsets, nonlinearity, and noise issues. This tutorial explores DCR's historical development, compares it with other receiver architectures, and addresses its inherent obstacles. DCR's potential for integration and compatibility with software-defined radio highlights its role in modern communication systems despite its technical complexities.

KISS703 is a 703 Hz narrowband digital mode for amateur radio, designed for simple, low-power operation without computers. A 500 Hz pilot tone ensures frequency alignment, replaced by unique tones for 37 symbols (letters, numbers, space). Built from common discrete components, it draws about 40 mA at 12 V, ideal for SOTA/IOTA use. The receiver uses amplification, wave shaping, and a pulse-counting frequency meter for manual decoding via a calibrated meter. Transmitter and receiver calibration involves marking meter positions for each tone, enabling fully self-contained messaging with minimal hardware in portable or fixed operations.

This page delves into the early history of radio and television, exploring the fascinating personalities and inventions that shaped the industry between 1870 and 1929. The author reflects on the pioneering work of figures like Thomas Edison, Guglielmo Marconi, and Nikola Tesla, highlighting the challenges and innovations that defined the golden age of radio. With a focus on a specific project involving a one tube AM radio, this article offers insights into the evolution of radio technology and its enduring impact on society. Ideal for hams and radio enthusiasts interested in the roots of modern communication.