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Construct the Peaberry, a SoftRock-compatible SDR transceiver. This project is aimed to build an amateur radio transceiver that operates on the medium or short wave bands

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.

Operating within the low-frequency spectrum, transformers serve critical roles in antenna systems, particularly for 160m applications. The resource details the construction and performance of 1:1 transformers built on BN-73-202 cores, emphasizing their use as hybrid combiners or phase inverters for RX antenna arrays. Measurements reveal that these transformers exhibit minimal losses, around 0.12 dB at 1.8 MHz, with variations based on wire type and number of turns. The analysis includes comparative data on transformer performance, highlighting the impact of different winding techniques on frequency response. Notably, the use of coaxial cable for winding improves bandwidth while maintaining low-frequency efficiency. The resource also discusses braid breaker transformers, which minimize inter-winding capacitance, achieving low losses around 0.21 dB at 1.8 MHz. These insights are crucial for optimizing low-band antenna systems, allowing operators to make informed decisions regarding transformer design and implementation.

WSJTX-Controller-v2, or Otto, functions as an assistant for the WSJT-X amateur radio program, specifically designed to enhance operational efficiency for weak signal digital modes. The software automates several key tasks, including call management, prioritizing DX stations based on user-defined criteria, and optimizing frequency selection within the WSJT-X interface. It requires a modified version of WSJT-X to function correctly, integrating directly with its core processes to provide augmented control. Otto supports various digital modes, facilitating auto-logging of contacts and generating specific alerts for desired stations or conditions. It is engineered to streamline the workflow for operators engaged in DXing and general weak signal communication, offering features like automatic CQ responses and intelligent band monitoring. The utility is not compatible with certain other amateur radio software and is explicitly noted as unsuitable for contest operations or the WSJT-X Hound mode, indicating its specialized focus on non-contest DX and casual operating. The project's GitHub repository provides the source code and documentation, allowing users to review its implementation and contribute to its development. The software's design emphasizes automation to reduce operator intervention during routine digital mode operations.

DXFile is a Windows shareware application designed for amateur radio operators, providing comprehensive log management capabilities. The software, developed in Pascal, facilitates real-time and deferred QSO entry, automatically populating fields like frequency, mode, and DXCC country based on user input and system time. It includes features for searching, modifying, and deleting QSO records, with options to sort logs by date, callsign, or entry order. The program offers various printing functions, including QSL card labels in multiple formats, and can generate standard logbook printouts. Beyond basic logging, DXFile integrates modules for tracking progress towards major operating awards such as DXCC, _IOTA_, WAZ, WAS, DDFM, and DIFM. It provides detailed summaries of contacts by band and mode, including graphical representations of HF traffic. A dedicated QSL Manager module assists in processing received QSLs, allowing users to mark confirmations and print multi-line QSL labels. The application also incorporates a DXCC list viewer, which can be updated to ensure accurate country and zone data for logging and award tracking. A distinctive feature is its HF propagation prediction module, which calculates optimal frequencies and signal levels for paths between **250 km** and **6000 km**, considering both E and F layer ionospheric conditions. This module helps operators determine the best times for long-distance contacts. Additionally, DXFile includes a _Web-Cluster_ interface, enabling connection to various DX cluster servers like DXLITE, DXSCAPE, and NC7J for real-time spot information.

Modification to an old cellular phone base station modules, with a fairly reduced output power (10 watts or so), the stock power amplifier modules will cover the 2.3 GHz and 2.4 GHz amateur radio bands.

The HB9CV antenna calculator aids amateur radio enthusiasts in designing antennas for VHF and UHF bands. By inputting the working frequency, users can obtain crucial dimensions like dipole lengths and distances. The tool, based on the HFSS antenna model, provides data on impedance, VSWR, and gain, optimizing front/back radiation ratios. It includes tips for fine-tuning using a Г-matching balun and compensating capacitor, ensuring effective performance and minimal VSWR for enhanced radio communications and direction finding.

This antenna works on 17, 20, and 30 meters, with the best bandwidth on 20 meters. The bandwidth on 17 and 30 is quite small but usable. There is a 20 KHz bandwidth on 20 meters.

HF digital mode transmissions, voice transmissions in HF and VHF Bands collected in several XLS files by Relic Radio communications

The **Nilex Morse Tutor** is an HTML5 web application designed to teach Morse code reception, adapting to user proficiency by adding new characters as readiness is detected. It prioritizes practice on less familiar letters, numbers, symbols, words, and phrases, while minimizing repetition of already mastered elements. The program offers multiple learning orders, including "Q7ZG..." (Ward/Jim's), "KMRS..." (PU5EPX/Koch), "KMUR..." (lcwo.net), "AENT..." (CWops CW Academy), "TEAN..." (Stephen C Phillips), "ANET..." (Vic VE3YT), and "ETI5..." (Ham Whisperer), alongside an alphabetical option. Users can customize the learning experience by enabling or disabling automatic progression, and selecting specific content categories such as numbers, symbols, words, phrases, QSO bits, Ham Radio Bands, X+Y=Z math, and units. Audio settings are adjustable for volume, speed (WPM), tone frequency, and keyshape/keying envelope, allowing for a personalized auditory environment. The interface provides visual feedback with blue bars indicating practice emphasis and gray bars for reserved characters, with clickable bars for manual character selection. Developed by "Nosey" Nick Waterman, VA3NNW, this tutor is based on earlier versions by Jim Wilson and a 1977 QST article. A significant October 2019 rewrite incorporated a new WebAudio sound library by AwesomeAidenW, improving offline functionality and mobile support. The content library was expanded to include 3000 top Google words, 2284+ General Service List words, ISO country codes, capital cities, US states, Canadian provinces, UK counties, common names, periodic table elements, quotes, Q-codes, electronic components, ham abbreviations, and example call signs. The software is distributed under the GNU GPL V2 license.

This project involves constructing a dual-band Moxon antenna, optimized for ham radio enthusiasts, with functionality on both the 10-meter and 6-meter bands. The antenna is designed to operate using a single 50-ohm feedpoint, acting as a mini-beam on 28 MHz (10 meters) and as a 2-element Yagi on 50 MHz (6 meters). Performance-wise, it offers a 4.0 dBd gain on 10 meters and 4.3 dBd on 6 meters, with impressive front-to-back ratios of 30 dB and 11 dB, respectively. Builders like Aleks (S54S) and Marcio (PY2OK) have successfully brought this design to life using the provided specifications. Aleks noted that bending the corners of the structure proved especially useful during assembly. The project comes with a detailed parts list, highlighting the use of aluminum tubes with different diameters and lengths to form essential components like the reflectors and radiators. For those looking to fine-tune the antenna, adjustments can be made by altering the length of certain parts that fit into larger tubes. The feeding system is equipped with a balun to accommodate different power levels, making the design versatile enough to handle outputs of either 300 watts or 1 kilowatt.

This document provides a detailed guide on constructing and mounting a folded dipol for the 146 MHz frequency in a vertical configuration to be used in Yagi antennas. The step-by-step instructions and diagrams included make it easy for hams to build and set up this type of antenna. Understanding and implementing this design can enhance the performance of radio communication for Amateurs operating in the 2-meter band. Whether you are looking to improve your signal strength or experiment with antenna designs, this resource offers valuable insights and practical information.

An Arduino Based Antenna Switch For The IC-7300 that monitors the band voltage from the rear accessory socket on the IC-7300. Two RF antenna relays are used to switch to the appropriate output.

NPR (New Packet Radio) is a custom amateur radio digital protocol, designed by F4HDK to transport bidirectional IP trafic over radio links on the 70cm band. This IP protocol is optimized for point-to-multipoint topology, with the help of managed-TDMA. Bitrate is up to 500kbps. Home Made modem has a built-in ethernet port to connect to PC. To boost power a DMR amplifier is required to reach 20W. This project is an extension of HSMM - Hamnet - AREDN networks

Otto enhances WSJT-X, the popular weak-signal digital modes program for amateur radio. It automates tasks like managing QSOs, prioritizing DX stations, replying to specific calls, and optimizing band usage. Otto works with a modified WSJT-X version (v2.7.0) to add advanced features such as directed CQs, automatic logging, and multi-stream replies. Its intuitive modes streamline operations, while safety measures ensure controlled transmissions. Ideal for DX enthusiasts, Otto improves efficiency and focus, making weak-signal operations more engaging and productive.

A basic introductionto APRS on HF Bands for radioamateurs and how to setup an APRS tracker using Argent Data Systems T3 Mini TNC device, configured and assemble ready for portable operations.

Amateur radio courses teach that in amplitude modulation, sidebands arise. This can be proven mathematically, and nowadays with an SDR one can easily see them.

The database of Chinese ham radios. We are here to show you that you do not need expensive kit from big brands to have fun with ham radio. With the explosion of open source designs, cheap manufacturing, and global delivery, you can now get on the bands and explore for less than ever before.

This article describes the construction of a simple dual-band VHF/UHF end-fed vertical dipole antenna designed for local repeater access using an Icom IC-705 radio. Built from a single piece of RG58U coaxial cable, the antenna consists of a 460mm exposed inner conductor, 450mm of intact coax, and a 9-turn choke balun wound on a 27mm former. Mounted on a 10m Spiderpole, the antenna achieves excellent SWR readings (<1.2:1 on 2m, <1.5:1 on 70cm) and provides effective coverage of local repeaters with unexpected reach into distant locations.

Hamradio_copilot is an open-source tool designed for DXers and contesters who need real-time situational awareness. It is ideal for operators who want to visualize propagation trends instantly rather than scrolling through raw text streams of cluster spots. Rally acting as a copilot for your station, this tool transforms raw data into actionable intelligence. By visualizing Signal-to-Noise Ratios (SNR) across different bands, it helps operators make quick decisions on which band to prioritize or where to point their antennas, effectively showing not just who is on air, but where the propagation is currently open from your location. This is a fantastic information for avid contesters. The software aggregates data from two primary services: - Reverse Beacon Network (RBN) via Telnet. - PSK Reporter via MQTT feeds. It processes this data to generate a comprehensive HTML report featuring SNR heatmaps and statistical breakdowns by ITU Zone. Users can filter data by specific zones or country codes (ADIF), analyze historic time ranges, and optionally integrate solar weather data. The complete source code is available on GitHub, allowing for community customization. It is written in Python and uses SQLite for data management.

Author is currently developing the HS4HF 4 Band HF Radio Transceiver with a 5.0-inch TFT display, following their previous HSM1 model. They are also working on the Radio HSDRA, an All Band SDR HF Radio Transceiver with unique features such as DSP Digital Modulation, 100W final power, automatic antenna tuner, and more. The development includes a wide 5.0-inch display, touch screen, and various advanced functionalities. Stay updated with the latest developments in the world of HAM radio with Hambuilder Team.

This article presents the C-Pole antenna project, a compact, ground-independent vertical antenna designed for amateur radio operators. It features a folded half-wave dipole configuration that eliminates the need for radials, making it suitable for various locations, especially in deed-restricted areas. The C-Pole offers efficient performance with a 2:1 SWR bandwidth of approximately 3%, and it can be easily constructed using common materials. Additionally, the article discusses practical aspects such as feed-point impedance transformation and balun design to optimize functionality and minimize losses.

1-watt 17-meter cw transmitter that was originally done about 10 years ago as a club project for RAMS, the Radio Amateur Megacycle Society. It uses a VXO, rather novel at the time. It also uses a bandpass filter at the output rather than the usual lowpass

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.

Ribbit is a novel digital text messaging mode for VHF/UHF communications for recreational and emergency use which radically increases the density of information transmitted by spectrum used. It leverages the computing power of the modern smartphone to increase the capabilities of any Handy Talkie without requiring any additional hardware or cable. A Ribbit message is fixed in duration at 1250 milliseconds. It is sent over audio modulation with a 2kHz bandwidth centered on 1.5kHz. It is preceded by 400ms of white noise to open analog squelch circuits.

Amateur radio enthusiast Jean-Paul Suijs discusses combating manmade noise (QRM) in radio signals using AI. Detailing experiments with phase-shifting techniques and the self-learning nature of AI, he explores AI-based audio processing apps for real-time noise cancellation during radio contests, demonstrating results on both medium wave and shortwave bands.

Four distinct amateur radio bands, specifically 40, 30, 20, and 15 meters, are addressed by a portable dipole antenna design. This antenna utilizes a manual switching mechanism, employing "fast-on" or flying connectors to change bands. The design is presented with an animated plan, illustrating how operators can adjust the operating frequency by opening and closing specific connections on the antenna elements. The resource describes a _4 savos dipol_ (4-band dipole) that can be shortened for specific band operation. It provides practical information for hams seeking to construct a versatile, multi-band wire antenna for portable operations or fixed station use. This design offers a straightforward approach to achieving multi-band HF capability without complex tuning units, making it suitable for field deployments like SOTA or POTA activations where rapid band changes are beneficial.

The J-pole antenna calculator helps users design custom J-pole antennas for specific frequency bands. It provides dimensions for key antenna sections based on the chosen frequency and material’s velocity factor. The calculator also offers insights into J-pole antenna mechanics, velocity factors, and mounting tips, making it ideal for enthusiasts creating antennas for amateur or mobile radio communications.

Over 15 amateur radio bands, from 160m to 70cm, are supported by the _DXTRON_ web cluster, providing real-time DX spotting information. This service integrates directly with the _QRZCQ_ API, allowing users to monitor activity across various modes including CW, Phone, Digi, RTTY, SSTV, and SAT. DXTRON displays critical spot data such as timestamp, spotter callsign, frequency, mode, DX call, and remarks, along with geographical details like Grid, DXCC, ITU, CQ zone, continent, and country. Developed by _DO5SSB_, DXTRON v1.42 offers a user-friendly interface for filtering spots by band and mode, catering to both casual DXers and serious contesters. The platform is designed for accessibility, providing a clear overview of current propagation conditions and active stations worldwide. This web cluster is a practical tool for hams seeking to identify rare DX, track contest activity, or simply observe band conditions. Its reliance on the QRZCQ API ensures a consistent flow of up-to-date spotting data, making it a reliable resource for real-time operational awareness.

This guide provides detailed information on designing a 5 Band Quad Antenna for ham radio operators. It covers the necessary materials, dimensions, and construction steps required to build the antenna. The guide aims to help hams optimize their antenna setup for maximum performance on five different bands. Whether you are a beginner or an experienced operator, this resource can assist you in creating an effective antenna system for your station.

The 222 MHz Transverter project, based on Zack Lau's (W1VT) original July 1993 QEX magazine design, provides an IF of 28 MHz for both transmit and receive paths. Rick Bandla (VE3CVG) contributed supplemental notes and construction details, including modifications to achieve 10 mW output power from an initial 4 mW PEP. The design incorporates three distinct boards: a Local Oscillator (LO), a Transmitter (Tx), and a Receiver (Rx), with an estimated parts cost of just over $150 CDN, significantly less than commercial kits. Construction involves both through-hole and surface-mount components, with specific guidance on mounting MAV and MAR devices, grounding techniques, and component selection. The project details include parts lists, schematics for the LO, Tx, and Rx, and board layouts. Troubleshooting advice emphasizes sequential testing, starting with the LO, then Tx, and finally Rx, using a 194 MHz and 222.100 MHz capable FM handheld for signal tracing. Further enhancements are discussed, such as an optional Tx driver stage to boost output to 100 mW and the potential modification of a Motorola Maxor 80 PA for 222 MHz SSB/CW operation. The resource also covers practical aspects like power attenuation pads for IF radios (e.g., FT817) and considerations for enclosure design, including repurposing a Maxor 80 case. Performance reports indicate successful 70 km contacts with only 4 mW output.

This blog post discusses the use of TV-type 75 ohm splitters and taps in 50 ohm systems on the amateur HF, VHF, and UHF bands. The author shares insights and tips on how hams can effectively utilize these components for their radio setups. Whether you are a beginner or experienced operator, this information can help you optimize your equipment and improve your radio performance.

The Amateur Radio Logbook ADIF File Analyzer available at loganalyzer.sv5fri.eu is a convenient web-based tool that allows you to upload your ADIF log and instantly generate a visual map of your QSO contacts along with detailed statistics—by band, mode, time, grid squares, DXCC, and more. It provides an intuitive overview of your operating patterns and performance without requiring any software installation.

Discover the best low band receive antennas for hams with limited space. Learn about the K9AY loop antenna and Shared Apex Loop Array, two alternatives to the traditional Beverage antenna. Understand the concept of Relative Directivity Factor (RDF) and compare the performance of different receive antennas. See how the Shared Apex Loop, patented by Mark Bauman (KB7GF), offers an RDF between 8 and 10dB. Find out how to optimize antenna performance and enhance your receive capabilities on 160, 80, and 40 meters. Explore the world of low band receive antennas with insights from WB5NHL Ham Radio.

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.

System Fusion is Yaesu’s implementation of Digital Amateur Radio, utilizing C4FM 4-level FSK Technology to transmit digital voice and data over the Amateur radio bands

This page provides a detailed step-by-step guide on building a 70 cm band repeater antenna for hams. The instructions are clear and easy to follow, making it suitable for both beginners and experienced operators. The antenna design is optimized for the 70 cm band, ensuring efficient communication for local repeater systems. Whether you're looking to improve your repeater setup or just starting out in amateur radio, this guide will help you build a reliable and effective antenna for your station.

SH6 is a versatile, browser-based utility designed for the detailed analysis and visualization of amateur radio contest logs. Supporting standard formats such as Cabrillo and ADIF, the tool allows operators to upload personal files via drag-and-drop or access a searchable public archive containing over one million logs. Key capabilities include comprehensive performance metrics, offering summaries of band breakdowns, QSO rates, and beam headings. Furthermore, SH6 provides advanced geographic visualization through interactive maps, analyzing contacts by country, zone, and continent. A standout feature is the side-by-side comparison mode, enabling users to contrast two distinct logs for strategic assessment. SH6 transforms raw log data into actionable insights regarding operator performance without requiring software installation.

TNXQSO.com offers a streamlined **log search** utility, specifically designed to consolidate QSL information for **DXpeditions** and special event stations. This online service aggregates data from prominent logging platforms such as Club Log, Logbook of The World (LoTW), and HRDLog, presenting a unified interface for radio amateurs to verify their contacts. The platform aims to simplify the process of confirming QSOs by providing direct links to the respective logging services, allowing users to quickly ascertain if their contact has been uploaded and confirmed. Users can input a callsign and band to retrieve immediate results, indicating whether a QSO is present in the linked logs. The service also supports DXpedition teams by offering tools for managing their own logs and QSL routes, without requiring an account for general log searching. This functionality proves particularly useful for DXers seeking rapid confirmation of rare contacts or for those managing their QSLing efforts across multiple platforms after a significant operating event.

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.

The quarter-wave Marconi working against ground is a popular and inexpensive antenna for 160 meters. A lot of newcomers to the band favor this simple antenna because it's easy to put up, it isn't too big, and it works.

The article enlightens radio amateurs on utilizing real-time space weather data to optimize HF communication. Navigating through Hp30 index, MUF, f0F2, and eSFI metrics, it explains their significance in band selection and propagation forecasting. With essential links and practical insights, enthusiasts learn to discern optimal conditions for high-band DX, low-band DX, and NVIS operations. The author's observations and antenna optimization tips enrich understanding for effective HF operations.

The analyser has been written to support the full range of SDRplay SDR radios including the new RSP1B. The analyser is capable of resolution bandwidths of less than 1Hz with sensitivity better than -145dBm. In addition to being able to run five separate traces, the analyser offers the ability to capture screen shots, export data in a range of formats and includes a versatile marker system. The analyser includes a comprehensive user manual and offers a very useful addition to any workbench.

The article details the design and construction of a four-band Moxon beam by a radio amateur. The beam, mounted atop a rooftop tower, aimed for gain over a dipole on 20 meters, cost under $500, and included additional bands. The design features fiberglass spreaders, four bands (20/15/10/6 meters), and a single feedpoint. The construction involved computer modeling, NEC source code, and specific dimensions. The article outlines the assembly, materials, and tuning process, including in-situ adjustments for optimal performance. Despite initial challenges, the beam improved signal strength and facilitated contacts on multiple bands, marking it as the best HF antenna the author has owned.

The TYT MD-2017 dual band VHF & UHF DMR portable radio review

The E6AF DXpedition to Niue (OC-040) in 2019 successfully activated a rare DXCC entity, providing thousands of contacts for the global amateur radio community. Operations focused on maximizing QSOs across various **HF bands** and modes, significantly contributing to the DXCC program. The team, led by SP9FIH, meticulously planned antenna deployments and station setups, including a specific focus on **Fox-Hound mode** for digital operations, to ensure robust signal paths and efficient pile-up management. Operational details included specific schedules for CW, SSB, and digital modes, aiming to accommodate different time zones and propagation windows. QSL information and log search functionalities were made available post-operation, facilitating confirmation for thousands of contacts. The expedition encountered logistical challenges, including power supply failure and strict COVID-19 travel restrictions that delayed licensing. Despite these hurdles, the E6AF and E6CI stations provided valuable contacts from Niue, a sought-after location for many DXers.

The resource details active HF radio networks maintained by foreign ministries for diplomatic communications, specifically listing operational schedules and frequencies. It currently covers networks for Bulgaria, Czechia, Egypt, North Korea, Russia, Tunisia, and the United States. The content provides specific operational parameters for these government-run shortwave stations. Information includes details on _legacy modes_ of operation and specific transmission times. The site also includes schedules for various _number stations_ which often utilize similar HF spectrum allocations. The data presented aids in identifying and monitoring these unique, non-amateur radio signals across the shortwave bands. Specific sections are dedicated to the networks of North Korea and the United States, offering granular data for each.

A 4 element Yagi Antenna for six meters band

A homebrew spectrum analyzer, the Specan, provides a crucial measurement capability often missing from the typical amateur radio shack, allowing for detailed analysis of RF signals up to 70 MHz. This double-conversion superheterodyne receiver design incorporates 112 MHz and 12 MHz intermediate frequencies, utilizing an _Si570_ as the local oscillator for fine tuning down to 1 Hz steps. It offers two resolution bandwidths: 300 KHz for broad spectrum sweeps and 1 KHz for precise close-in distortion measurements, achieving an 80 dB spur-free dynamic range at 1 KHz resolution. The project, a reboot of the classic _W7ZOI/K7TAU_ design from November 1998 QST, integrates an _Arduino_ microcontroller for controlling the Si570, managing a front-panel LCD, and communicating with a PC for spectrum plotting. This approach significantly reduces cost compared to commercial units, making advanced RF diagnostics accessible to homebrewers. The Specan can measure carrier suppression, VFO cleanliness, antenna VSWR, transmitter harmonics, and filter passband shapes, providing insights beyond what an oscilloscope or frequency counter can offer. Construction emphasizes modularity and careful shielding, with each stage built and tested individually on unetched copper clad board. The design includes detailed instructions for integrating the Arduino, building the Si570 oscillator, and aligning the various modules, often using the Specan itself for calibration. It requires a well-regulated linear power supply and can be built with common tools and readily available components, making it a practical and rewarding endeavor for those looking to enhance their RF test bench.