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This page provides guidance on designing an End-Fed Half-Wave (EFHW) or Random-Length antenna for amateur HF bands, such as 80 or 40 meters. The content explains how to optimize the antenna for multi-band use and match it to a 50-ohm system using an unun. Hams can generate radiation patterns, VSWR charts, and antenna current diagrams for their customized antenna designs. Understanding how antenna dimensions affect performance is essential for successful field operations. The page caters to ham radio operators looking to build efficient and effective HF antennas for their stations.

Details the construction of a Copper Cactus Dual-Band Super J-Pole Antenna, providing specific measurements for 1/2-inch copper tubing sections, including a 57-1/2-inch long section and a 19-inch short section, along with a 42-inch piece of 3/16-inch or 1/4-inch soft copper tubing for the matching stub. It covers soldering techniques for copper fittings, drilling an SO-239 panel mount coaxial fitting, and securing feed point connections with stainless steel adjustable band clamps. The resource specifies materials such as Schedule M 1/2-inch copper tubing, various copper fittings, a hardwood dowel or Fiberglas rod for insulation, and #14 stranded copper wire for the feed point. The guide simplifies the J-pole feed point by using an SO-239 fitting with an elongated mounting hole and band clamps, noting an optimal feed point distance of approximately 3 inches above the crossbar for proper impedance matching. It recommends a 4-turn coax choke, 5 inches in diameter, placed within 3 to 4 inches of the feed point for 2-meter operation to mitigate RF on the feedline. The project emphasizes weather sealing with silicon or butyl rubber compound and clear lacquer for durability and appearance.

This article provides an overview of setup Direwolf and QtTermTCP for HF packet radio operations. It covers important tasks such as setting up a Direwolf TNC, connecting with stations, and engaging in packet-based chat (K2K). It also looks at how to use nodes as relays and access basic BBS services. The paper also includes HF packet network etiquette recommendations and a description of how to handle common packet transmission issues, making it a useful resource for amateur radio enthusiasts.

Illustrates the construction of a mini ununtenna, focusing on practical design elements and component specifications for amateur radio operators. The guide covers the winding of the unun transformer, selection of appropriate ferrite core material, and integration of the radiating element. It specifies wire gauges, core dimensions, and connection points, providing a clear pathway for replication by hams. Compares the ununtenna's performance characteristics against other common wire antennas, highlighting its compact footprint and broadband capabilities. It discusses impedance matching considerations and offers insights into optimizing the antenna for various HF bands, making it suitable for portable operations or limited space installations.

The XX9D Log Online provides a direct log search function for the DXpedition to Macao, specifically detailing operations conducted in 2017 and 2019. This service allows amateur radio operators to verify their contacts (QSOs) with XX9D, a critical step for QSL card management and award applications. Users are explicitly advised to consult the online log to prevent duplicate contacts on the same band and mode, optimizing efficiency during active DXpedition periods. This online tool supports the "DX Code Of Conduct," promoting ethical operating practices within the amateur radio community. The platform facilitates the Online QSL Request System (OQRS), streamlining the process for requesting QSL cards without the need for traditional bureau or direct mail methods. Operators are instructed to defer OQRS submissions until the conclusion of the DXpedition, ensuring all logs are finalized. The log search interface is powered by CMSimple, a content management system, indicating a straightforward, database-free web application. The resource is designed for ease of access, providing a clear method for DXers to confirm their contacts and manage QSL requests efficiently.

Four _Headway 38120_ LiFePO4 cells form the core of an 8AH 12V battery pack, designed for reliable emergency and field power in amateur radio operations. These batteries offer significant advantages over traditional lead-acid types, including a lifespan up to **10x** longer in charge/discharge cycles, lower internal resistance for faster recharging, and a flatter discharge curve that maintains voltage stability during use. Their inherent safety, being a flame-retardant technology, makes them a preferred choice for portable applications. Proper configuration, including parallel/serial setups, and careful charging/discharging protocols are crucial for maximizing battery life. Each cell has a nominal voltage of 3.2 volts, with a maximum charge voltage of 3.65 volts. A Battery Management System (BMS) is highly recommended to prevent overcharging or deep discharging, safeguarding the cells. The project emphasizes safety, noting the batteries' high short-circuit capacity of **200 AMPS** and the critical importance of incorporating an inline fuse between the battery pack and the load. Components like the battery holder, buss bars, and a suitable case are also detailed.

The DX Jungle SatTracker is an interactive online tool designed for real-time amateur radio satellite tracking. It incorporates live Doppler correction, AMSAT satellite status, and pass predictions for various active amateur radio satellites such as ISS, SO-50, FO-29, and RS-44. The platform calculates real-time uplink and downlink frequencies, adjusting for Doppler shift, and displays satellite footprints and orbital paths on a map interface. Users can select specific satellites and input their grid square for localized pass predictions. This service integrates WebSDR support, allowing users to listen to satellite passes live without requiring a physical radio, and offers Companion radio control capabilities. Orbital data is sourced from CelesTrak, while radio frequencies are derived from AMSAT and SatNOGS. The interface provides options to filter for FM repeater-only satellites and displays active passes, ordered by the next available pass, facilitating timely operational planning for satellite enthusiasts.

Operating on the HF and VHF bands, the URE WebCluster serves as a real-time DX spotting network for amateur radio operators. It aggregates DX spots from various sources, presenting them with detailed information such as DX callsign, frequency, mode, and spotter details. The platform integrates essential propagation data, including current solar indices like _K-index_ and _A-index_, alongside visual propagation maps, which are crucial for planning long-distance contacts. Users can submit new DX spots, contributing to the collective intelligence of the amateur radio community, and filter existing spots by band, mode, or callsign, enhancing operational efficiency. This resource enables operators to monitor band openings and identify active DX stations, significantly aiding in _DXCC_ pursuit and contest operations. The integration of solar-terrestrial data directly within the cluster interface allows for immediate correlation between propagation conditions and observed DX activity, a feature not universally present in all web clusters. By providing both raw spot data and contextual propagation information, the URE WebCluster offers a practical tool for real-time decision-making during operating sessions, allowing hams to quickly adapt to changing band conditions and target specific _DX_ entities.

This page discusses the CLEFHW (Coil Loaded End-Fed Half-Wave) antenna, a portable variation of the popular EFHW design for ham radio operators. The article explains how the CLEFHW allows for backpack portable operation without the need for trees or poles, making it ideal for POTA activations and rapid deployment scenarios. The author details the design, optimization for 20m band, and compares efficiency to full-length wire antennas. Suitable for hams interested in portable antenna solutions and quick setup options for amateur radio activities.

This article explores the marriage of amateur radio and bushcraft, advocating the pleasure of setting up a portable station in nature rather than operating from the confines of a vehicle. The Parks on the Air (POTA) programme is highlighted as a catalyst for outdoor radio activities. The author shares his experiences and techniques, from transporting equipment into the wilderness to setting up shelters and antennas. Knot tying skills and the use of frogs are emphasized for efficiency, and a unique method for launching wire antennas is described. The article emphasizes the synergy between amateur radio and bushcraft skills, enhancing the enjoyment of radio operations in wilderness environments.

The Icom IC-9700 transceiver, a popular choice for VHF/UHF/1.2 GHz operations, gains enhanced remote control capabilities through Pycom Radio Controller. This software provides direct _CI-V based control_, enabling operators to manage frequency, mode, memories, and tones from a connected computer. It integrates a built-in rigctl server and supports popular satellite tools like Gpredict and SatPC32, facilitating full duplex Doppler control for satellite passes. Key features include real-time meters, a waterfall display, and remote RC-28 integration. Designed for practical amateur radio use, the application streamlines voice and digital satellite operations. It allows for full duplex remote Doppler control, crucial for maintaining accurate frequencies during satellite contacts. The software also incorporates callsign lookup and logging functions, alongside enhanced memory management. Documentation pages offer configuration guidance and operating examples, ensuring users can effectively set up and utilize the software for their satellite communication needs, potentially improving success rates for contacts and contests.

This page explores the world of Software Defined Radios (SDRs) in the context of amateur radio. It discusses how SDRs have revolutionized the hobby by reducing costs and enabling remote operation. The article provides ideas for projects and experiments that hams can undertake with SDR technology, highlighting the educational and experimental opportunities it offers. It also mentions specific examples of SDR projects like the Stoke on Trent SDR and SDR.HU. The content is aimed at amateur radio operators looking to explore and harness the potential of SDRs in their stations.

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.

RadioLog is a free amateur radio logbook software for Windows 10/11 (x64) that integrates QSO logging with real-time DX Cluster spots and _RigControl_ capabilities. It supports ADIF, eQSL, and LoTW for logging and export, along with specific modules for contest operation, including automatic scoring and _Cabrillo_/EDI export for HF and VHF contests. The software also features a dedicated portable mode for SOTA, POTA, WWFF, and CB/11m activations, offering a distinct logbook for these activities. The application includes an integrated _RTL-SDR_ auxiliary monitor for visual and audio support during operation, and offers three CAT connection methods: direct RadioLog control, Hamlib managed by RadioLog, or an external rigctld server. Recent updates, such as those in v4.0.2, focus on interface polish, consistent dark theme application, and layout bug fixes, including VFO frequency display with thousands separators. The software also provides reciprocal synchronization with QRZ.com Logbook, allowing both upload and download of QSOs, and supports various digital voice modes like DMR, C4FM, D-STAR, FreeDV, and M17.

Operating Slow Scan Television (SSTV) often requires specialized software to encode and decode images for transmission over amateur radio frequencies. The _MMSSTV_YONIQ_ project provides an updated iteration of the widely used _MMSSTV_ software, originally developed by JE3HHT, incorporating modern functionalities requested by the SSTV community. This version integrates the _Omni-Rig_ system for seamless transceiver control, supports both Spanish and English interfaces, and enables direct data downloads from QRZ.com, streamlining logging and contact management for operators. The software also includes practical enhancements such as frequency memory storage, compatibility with various digital logbooks, and a visual indicator for image transmission and reception progress. Significant improvements have been made to image reception settings, allowing for more effective decoding even on systems with limited PC resources, though it can be configured for higher performance on modern machines. The development involved new code and modifications to existing source code, released under a GNU license. Installation instructions are provided, noting that the initial setup defaults to Spanish but can be easily switched to English. The project emphasizes its role as a continuation of JE3HHT's original work, aiming to keep SSTV operations current with 21st-century amateur radio practices. Support for new features is available through the MMSSTV forum on Groups.io.

This article is from the book Ham Radio For Dummies and features some tips for portable amateur radio operations, on Field Day or generic outdoor operation, like selecting the proper antenna and portable power.

A 5/8-wavelength vertical antenna for 2-meter FM operation is detailed, focusing on eliminating loading coils by utilizing a series inductor to cancel capacitive reactance at the feed point, thereby presenting a 50-ohm impedance match. The design illustrates three basic configurations, including a method employing a short-circuited coaxial stub for inductance, as implemented by K4LPQ. An alternative design is presented where the center conductor of the stub is extended one-quarter wavelength, creating a signal-frequency short and allowing for an insulated wire stub to develop the required series inductance. The article provides electrical theory and mechanical considerations for building the antenna, emphasizing the adjustment of stub length for proper impedance matching. This technical documentation is intended for amateur radio operators interested in homebrewing VHF antennas, offering practical insights into impedance matching techniques for vertical radiators.

DXContest.org provides a real-time DX cluster, integrating advanced spotting capabilities with features like _propagation maps_, _PSKReporter_, and the _Reverse Beacon Network_. This platform enables radio amateurs to monitor DX activity, apply sophisticated filters to spot data, and even utilize CAT control for their transceivers directly through the web interface. The service is designed for immediate utility, offering free access without requiring user registration. Users can send DX spots, control their radio via CAT, and consult a contest calendar. The platform also provides traditional Telnet access for those preferring client-based cluster interaction. Developed by Pascual R. Salas Vidal, EA5WU, the service aims to be a comprehensive tool for real-time DX operations and contest participation, offering a blend of modern web features and classic cluster functionality.

The Pikes Peak Radio Amateur Association (PPRAA) serves as an ARRL Special Service Club, providing a calendar of events and activities for its members and the wider amateur radio community. The resource details upcoming events such as the USS Pueblo Memorial Museum Ships Weekend activations, a Cubical Quad Antenna Workshop, LARCFest, and various hamfests including Dayton Hamvention and Duke City Hamfest. It also lists on-air activities like a FreeDV digital voice mode event on 10 meters, a Black Friday Simplex Event on 2M and 70cm, and a 10m event for Technician class operators, emphasizing SSB privileges from 28.300 to 28.500 MHz. The PPRAA's event schedule includes educational opportunities like a Technician Class and a Soldering Workshop, alongside social gatherings such as the PPRAA Picnic and Car Show. Past event summaries highlight successful activities like the 2024 Megafest Raffle, Winter Field Day, and multiple fox hunts utilizing frequencies like 147.420, 147.480, and 147.540 MHz. The club actively supports POTA activations, exemplified by their AF0S park activation at Cheyenne Mountain State Park, and participates in historical commemorations like the USS Pueblo Memorial operations, demonstrating a broad engagement across various amateur radio facets.

_Icom_, _Yaesu_, and _MFJ_ are among the renowned brands available at R&L Electronics, a dedicated store for amateur radio enthusiasts. The store provides a diverse selection of equipment, catering to both novice and seasoned operators. From amplifiers and preamps to antennas and tuners, the store ensures a comprehensive inventory to meet various operational needs. Customers can also find essential components like cables, coax, and connectors, crucial for setting up and maintaining effective radio stations. In addition to new equipment, R&L Electronics offers used items, providing budget-friendly options without compromising on quality. The store's inventory includes test equipment and tools, vital for troubleshooting and optimizing radio performance. Tower components are also available, supporting those involved in more advanced setups. The website facilitates easy access to product information, shipping details, and order tracking, enhancing the shopping experience. R&L Electronics stands out by offering a variety of products that cater to different preferences and budgets, ensuring that every amateur radio operator can find the necessary equipment to enhance their setup.

This article presents a novel Top Loaded End-Fed Half-Wave (TLEFHW) antenna design for 20-meter ham radio operation. The antenna features a compact 14-foot vertical radiator with a capacitance hat configuration, eliminating the need for radials or ground systems. Using EZNEC modeling and field testing, the design achieves a 1.5:1 SWR across the 20m band with a 4.11 dBi gain. Key features include quick deployment, lightweight construction, and directional radiation pattern with 110-degree beamwidth. The design, while requiring a 45-foot footprint due to the top hat, offers an effective portable solution for amateur radio operators seeking a no-ground, no-tuner 20m antenna option.

Improving callsign recognition and copying skills is fundamental for effective amateur radio operation, particularly in high-stress environments like contesting or DXing. The CW4EVER Callsign Training Platform provides a focused environment for operators to hone these abilities. It offers three distinct training modes: a Typing Trainer for visual recognition, an SSB Trainer for voice callsign practice, and a CW Trainer for Morse code proficiency, allowing users to tailor their practice to specific operational needs. Operators can select training durations of 1, 3, 5, or 10 minutes, providing flexibility for quick drills or extended practice sessions. For CW training, the platform allows granular control over parameters such as CW speed, adjustable up to **80 WPM**, pitch in Hz, and weight in percentage, enabling personalized learning curves. The system stores operator preferences locally and includes server-side anti-cheat protection, stricter callsign validation, and automatic score archives, ensuring fair competition and persistent training history. Recent enhancements include separate saved CW preferences per operator and _MY DXCC_ ranking positions. The platform also tracks global statistics, including total attempts worldwide, unique callsigns encountered, and total training hours logged, offering a broad perspective on user engagement and progress. These features collectively support operators in achieving higher accuracy and speed in callsign reception.

The _DX EXPLORER_ blog serves as a personal chronicle of amateur radio experiences, particularly emphasizing homebrew projects and DIY radio equipment. It provides insights into constructing various transceivers and receivers, such as the Minimalist CW Transmitter and the Sputnik Regenerative Receiver, offering practical guidance for those new to the hobby. The content often details the assembly and operation of low-cost kits like the $3 Pixie Transceiver, demonstrating accessible entry points into radio construction. Beyond building, the site also features reviews of commercial gear, including the Tidradio TD-H8 Radio, providing an operator's perspective on performance and utility. The author, YO6DXE, shares a learning journey, aiming to inspire fellow enthusiasts to engage with the technical aspects of amateur radio. This resource covers a range of topics from basic circuit explanations to practical operating tips, fostering a deeper understanding of radio principles. The blog's focus on personal experimentation and project documentation makes it a relevant resource for hams interested in hands-on learning.

CQ Amateur radio 2019 article analyzing possible impacts of Artificial Intelligence in Amateur Radio operations. How to integrate AI in the radio shacks.

The CW keyer with memories, inspired by SOTA activities, features three on-the-fly programmable memories for hands-free operation during logging or specific calls. Designed for low power consumption, it uses AAA batteries and an Arduino Mini, optimized for minimal energy use with a sleep function. The compact design fits in a small TEKO box, with a printed circuit board for easy assembly. The keyer includes customizable software for various CW modes and settings, programmable via paddles and command mode. It's an efficient, portable solution for amateur radio enthusiasts seeking enhanced CW functionality.

Demonstrates a cloud-based suite of tools for amateur radio operations, eliminating local software installation. The platform integrates a comprehensive logbook with import/export functionality, an _eMap_ application displaying DX spots, user locations, and grayline data, alongside a dynamic band map derived from DX cluster information. It also provides a _vQSL_ system for QSL management and a mailbox with QSO verification. Users can access a Web DX cluster to monitor spots and _DXCC_ status, or connect via Telnet using external programs like _Logger32_ or Ham Radio Deluxe. The cluster supports advanced spot filtering by QRG, spot call, spot from, and origin, with configurable mail alerts based on IARU zone filters. Additional features include a real-time chat for skeds, azimuth/distance calculations from a user's QTH (with QRA locator), a search engine for spot and logbook databases, a band status matrix, and a propagation tool for MUF calculations, leveraging data from N0NBH.

145 MHz is the target frequency for this 2-meter Skeleton Slot Yagi Stack antenna project. The design focuses on feeding two stacked Yagi antennas using a skeleton slot radiator, which is a unique approach for VHF enthusiasts. The project details the construction process, including the loop tapered matching section for impedance matching, ensuring optimal performance. The use of specific components like the EH789 element holder and MB456 main mast bracket is highlighted, providing clarity on the assembly process. The construction utilizes 20x20 box aluminum bar for durability and precision. Key dimensions, such as the element length (ER-ED4) and main boom spacing (MM123), are meticulously outlined. This attention to detail aids in replicating the antenna design accurately. The downloadable PDF offers comprehensive instructions, making it accessible for amateur radio operators interested in VHF antenna construction. This project is particularly beneficial for those looking to optimize their 2-meter band operations. The inclusion of a skeleton slot radiator and loop tapered matching section demonstrates advanced techniques in antenna design, catering to both intermediate and advanced builders.

In 2004, Carl Luetzelschwab, K9LA, wrote a guide on using W6ELProp for radio wave propagation predictions. This tutorial, translated for broader accessibility, explains initial setup, configuration, and daily use. It emphasizes using mean solar index values for accuracy, helping users effectively predict and interpret propagation for improved amateur radio operations.

Operating amateur radio repeaters involves understanding frequency offsets, CTCSS tones, and the basic signal flow through a repeater system. This resource details the fundamental concepts of repeater operation, including the distinction between input and output frequencies, the role of **CTCSS (Continuous Tone-Coded Squelch System)** for access, and the typical frequency bands utilized for local communication. It clarifies terms such as "simplex" versus "duplex" operation and provides a diagram illustrating the signal path from a handheld transceiver to a repeater and back to another station, emphasizing the range extension repeaters offer. The article further explains practical aspects like identifying a repeater's offset (e.g., +600 kHz for 2-meter band) and the necessity of programming the correct tone. It compares the operational benefits of using repeaters for local communication over direct simplex contacts, highlighting how repeaters overcome line-of-sight limitations. The content is structured to assist new licensees in confidently making their first repeater contacts, providing a foundational understanding of how these critical infrastructure components facilitate wider area coverage for VHF/UHF amateur radio.

QSL Digest presents a curated collection of daily news and commentary relevant to the amateur radio community, drawing content from various sources. The platform features articles on diverse subjects such as **contesting**, new equipment releases, and current propagation conditions, alongside updates on satellite operations and the activities of prominent amateur radio operators. It functions as a community-driven hub, aggregating information to keep hams informed about developments across the hobby. The site distinguishes itself by offering special features and a regular comic, adding unique elements to its news delivery. Content is sourced from the community itself, fostering a collaborative environment for information sharing. Each entry provides a concise summary and a direct link to the original source, allowing readers to quickly access detailed articles and stay current with the latest happenings in the amateur radio world.

This article discusses the evolution of portable amateur radio operations, focusing on optimizing backpack-carried equipment for outdoor use. The author shares his journey from using wheeled carts to developing an innovative backpack-mounted antenna system, emphasizing the transition from high-power (QRO) to low-power (QRP) operations to reduce weight. The piece details practical solutions for antenna mounting, equipment selection, and portable operations in challenging terrain, particularly along Ontario's Niagara Escarpment. The author's approach prioritizes mobility and functionality while maintaining effective radio communications in remote locations.

This **PDF report** documents a _maritime mobile_ DXpedition operating from the _Southern Ocean_ near Antarctica, detailing antenna deployment strategies on a sailing vessel. It addresses power management systems for remote operations and propagation characteristics specific to polar regions on **20m and 40m** bands. Operational strategies include managing high-density pileups using split frequency operation and maintaining signal integrity during periods of high aurora activity. Equipment considerations cover specific transceiver models like the Icom IC-7300, antenna types optimized for marine vessel installation, and battery power systems for extended periods without shore power. The resource also examines the use of satellite communication for real-time log uploads and QSL confirmation from remote locations, and discusses mitigating signal degradation from ice accumulation on antennas. DXZone Focus: PDF report | Maritime Mobile DXpedition | Polar Propagation | Split Frequency Operation

Operating on the 60m band requires specialized antennas, and the 2 Element HB9CV, also known as the _ZL special_, excels in this domain. With a gain of **7.3 dBi** when phased at a 162-degree shift, it rivals traditional 3-element Yagi antennas, making it a solid option for enhancing 60m operations. The construction process is thoroughly detailed, providing insights into its performance and practical applications. Real-world comparisons demonstrate that the HB9CV antenna outperforms long Beverage antennas by an average of **5.5 dB** in reception, showcasing its effectiveness in various conditions. Insights from Mr. Cebik's analysis further validate its design, confirming its capability to maximize communication on the 60m band.

The Central States VHF Society, Inc. (CSVHFS) is a not-for-profit organization chartered in the state of Missouri. It was begun in the mid-1960s to foster amateur radio operation on the bands above 50 MHz.

Outlines the essential steps for successfully activating a **Summits on the Air (SOTA)** peak, providing a structured approach for amateur radio operators participating in this popular award program. It details crucial pre-activation planning, including navigating the SOTA website, setting up a SOTA Data account, and consulting the **Association Reference Manual (ARM)** for specific regional rules and peak information. The guide also covers using mapping resources like adventureradio.de and lists ofjohn.com to identify suitable summits and check access conditions. The document emphasizes safety during the activation, advising operators to monitor weather, carry rain gear, and plan ample time for the ascent and descent. It specifies the **4-QSO minimum** requirement within the Activation Zone and recommends calling "CQ SOTA" on traditional QRP or VHF calling frequencies. The guide also suggests using local 2m FM repeaters for safety communications and spotting, while clarifying that repeater QSOs do not count for SOTA points. Post-activation activities include submitting logs to sotadata.org.uk, uploading trip reports to share experiences with future activators, and promoting SOTA participation on various reflectors. The guide highlights the program's appeal through its awards system for both activators and chasers, encouraging new participants in North America.

Hamword is a Winlink-based game that mimics the popular five-letter word guessing game, Wordle. The goal of this game is to give hams a way to practice their Winlink skills while having some fun guessing an unknown five-letter word. The only thing you need to play the game is an amateur radio license and an operational Winlink account.

SDR Television v1.0 operates as a DVB-S2 / AAC / H264 / H265 program, specifically engineered for QO-100 satellite Digital Amateur Television (DATV) operations. It provides a full-duplex solution on modern x86 computers running Windows 10 or 11 (64-bit, 8+ cores, AVX2 support recommended), leveraging DLLs from _SDR Console_ for control of devices like _Pluto_ and _LibreSDR.TV_. The software requires installation of the SDR Radio kit for wideband mode support. Initial development focused on a proof-of-concept for QO-100, with future enhancements planned to include H266 / AV1 / Opus codecs and an improved cross-band user interface. The current stable release functions reliably for QO-100 DATV. Users must install the SDR Radio kit, followed by the SDR Television kit, into the same directory. Support inquiries are handled via the SDR-Radio.com mailing list, ensuring direct assistance for operational questions.

Detecting stray RF voltages on station grounds, chassis, and interconnecting cables is crucial for preventing program and hardware failures in the shack. This article details the construction and application of an LED RF V-probe, which offers significantly higher sensitivity compared to conventional neon lamp indicators. The probe leverages two specific properties of modern red LEDs: their ability to glow at microampere currents and their rectification capability at frequencies up to tens of megahertz. The design features a simple circuit with two LEDs, allowing for indication of both positive and negative RF voltage half-waves. The minimum detectable RF voltage is approximately 2 V, a substantial improvement over the 40-60 V threshold of neon bulbs. The resource illustrates the probe's physical construction on a PCB and provides a direct comparison demonstrating its superior sensitivity in detecting RF fields near a coil. Two operational modes are described: a non-contact mode for high RF voltages (above 15-20 V) and a direct-contact mode for measuring lower RF voltages, with a safety caution for the latter. Practical examples show the probe's use in analyzing RF voltage distribution across a radio station setup at 1.84 MHz and 24.9 MHz, revealing insights into common-mode current issues and the effectiveness of mitigation strategies like adding radials.

Assessing the ICOM IC-R9000 communications receiver, this review details its operational parameters and user experience for radio enthusiasts. Introduced in 1985, the IC-R9000 covers a broad frequency spectrum from 0.1 MHz to 1999.8 MHz, making it suitable for a wide array of listening activities from medium wave (MW) to VHF/UHF. Key performance metrics include a dynamic range of **102 dB** with the narrow SSB filter, crucial for discerning weak signals in crowded bands, and its substantial physical dimensions of 424 x 150 x 365 mm and 20 kg weight. The receiver's architecture supports various modes, though it notably lacks synchronous detection, a feature often desired for improved AM reception under fading conditions. It incorporates 1000 memory channels and robust scanning capabilities, facilitating efficient monitoring across its extensive frequency range. This analysis provides insights into the IC-R9000's capabilities and limitations, offering a historical perspective on a significant piece of amateur radio and shortwave listening hardware.

Enables digital radio transceivers to function as versatile data communication nodes, supporting applications like _Reticulum_ networking, messaging with Sideband, and acting as a LoRa-based KISS-compatible amateur radio TNC. This firmware transforms off-the-shelf development boards into powerful, long-range data radios, facilitating robust communication over significant distances, potentially achieving **hundreds of kilometers** with optimal setups. It supports a range of hardware, including unsigned.io's Handheld RNodes (v2.x and v1.x), LilyGO T-Beam v1.1, LilyGO LoRa32 (v2.0, v2.1), and Heltec LoRa32 v2 devices. Compatibility extends to transceiver modules utilizing Semtech SX1276, SX1278, SX1262, SX1268, and SX1280 chips, provided they have an SPI interface and exposed interrupt pins. Installation is streamlined via the `rnodeconf` utility, part of the `rns` package, simplifying the flashing process for users. The project operates under the GNU General Public License v3.0, promoting open development and user freedom. It encourages community involvement in building and deploying RNodes for various purposes, from personal communication to establishing resilient, decentralized networks. The firmware's design emphasizes flexibility, allowing for diverse configurations to suit specific operational requirements.

Callook provides a **USA amateur radio callsign lookup service** with data current as of March 25, 2026. The platform allows users to search for valid callsigns and retrieve detailed information, including geographic coordinates sourced from the Bing Maps API. A mathematically calculated **grid square** is derived from these coordinates, though accuracy is not guaranteed due to reliance on external services. The service supports multiple access methods, including a browser search plugin, direct API access with a reference, and plain text output for integration into other applications or scripts. This tool facilitates rapid identification of US amateur radio operators, offering an alternative to other callbook services. Its API access enables developers to integrate callsign lookup functionality into custom applications, streamlining data retrieval for logging software or contest management. The direct presentation of FCC data, combined with grid square calculation, assists DXers and contesters in verifying contact information and location details during on-air operations.

Examines the historical context of amateur radio, specifically focusing on Guglielmo Marconi's pioneering wireless transatlantic signal reception at Signal Hill, Newfoundland, in 1901. It describes the operation of a contemporary remote radio station at Signal Hill, utilizing the special event call sign _VD1M_ issued by Innovation, Science and Economic Development Canada. The content recounts a specific contact from Signal Hill, reporting a signal strength of 5 by 9 to a station in Sarnia, Ontario, which received the signal at 3 by 3. The narrative also introduces the concept of 'Marconi chasers' who endeavor to replicate historical transmission methods. Further, the resource discusses general amateur radio operating procedures, the evolution of the hobby, and its critical role in emergency communications, citing examples from hurricanes _Irma_ and _Maria_ in 2017 and the conflict in Ukraine in 2022.

Operating amateur radio satellites presents unique challenges, particularly concerning antenna design and signal propagation. Juan Antonio Fernández Montaña, EA4CYQ, recounts his three-year journey into satellite communication, starting with initial guidance from EB4DKA. His early experiments involved a portable 1/4 wave VHF antenna with four 1/4 wave ground planes, designed for hand-held use to adjust polarity. This setup, paired with an FT-3000M transceiver, allowed full-duplex operation on **VHF** transmit and **UHF** receive, proving effective for early contacts on satellites like AO27, UO14, and SO35. EA4CYQ's experience highlights the critical role of coaxial cable loss and antenna polarization. After encountering significant signal degradation with longer RG213 runs, he experimented with a 1/2 inch commercial cable, noting improved reception but persistent fading due to varying satellite polarities. This led to the construction of an **Eggbeater II** antenna, an omnidirectional UHF design offering horizontal polarization at the horizon and circular right polarization at higher elevation angles. Subsequent modifications resulted in the directional **TPM2** antenna, which provided sufficient gain for LEO satellites with a wide 30-degree lobe, enabling consistent contacts from his home station. The article concludes with practical insights on the performance of the Eggbeater II for both UHF and VHF, and the TPM2 for UHF, emphasizing their utility for portable and fixed operations. EA4CYQ's journey underscores the iterative process of antenna development and the importance of adapting designs to overcome real-world propagation challenges in satellite communications.

Twenty 1-watt carbon film resistors are configured in parallel to construct a 50-ohm **dummy load** for amateur radio applications. The design incorporates a heatsink for thermal dissipation and an **SO-239 connector** for RF input, making it suitable for QRP operations. This budget-friendly project details component selection, soldering techniques, and mounting procedures, achieving a continuous power rating of 10 watts and intermittent handling of up to 100 watts across HF and VHF frequency ranges. The resource provides a step-by-step guide for assembly. This construction offers an economical solution for essential shack tasks such as antenna tuning, transmitter testing, and SWR meter calibration without radiating an RF signal. The utilization of readily available components significantly reduces the overall build cost compared to commercial alternatives, providing radio amateurs with a functional and reliable test accessory. While specific VSWR measurements are not provided, the design prioritizes practical utility for low-power transceiver diagnostics and general RF experimentation.

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.

OpsLog is a modern amateur radio logbook application for Windows, designed to consolidate station operations into a single, integrated interface. It provides fast, single-strip QSO entry with automatic lookup from QRZ.com or HamQTH, populating callsign, name, QTH, and grid square. The software offers real-time CAT control supporting OmniRig, native FlexRadio/SmartSDR, Icom CI-V (via USB or internet), and TCI protocols. Key logging features include ADIF 3.1.7 compliance, offline DXCC resolution, a worked-before matrix, and dupe detection. It also incorporates a great-circle map for short/long path calculations and a clickable rotor compass, displaying antenna direction accurately. The application integrates DX cluster functionality with multiple server connections, band map spot display, and customizable alert rules for callsign, country, band, mode, or spotter, delivering notifications via sound, on-screen alerts, and email. OpsLog tracks numerous awards such as DXCC, WAS, WAZ, WAC, WPX, IOTA, POTA, SOTA, WWFF, and DDFM, with synchronization capabilities for ClubLog, LoTW, QRZ.com, and eQSL. For contesting and multi-operator environments, it offers serial number auto-fill, enforced contact windows, live dupe flagging, and shared MySQL logbook support for real-time status updates among operators. Additionally, it includes a QSL card designer with automated layout suggestions.

DK4MJ's blog details numerous POTA activations and outdoor amateur radio operations, predominantly from Germany. The content focuses on practical experiences in the field, often involving portable setups and antenna deployments for various bands. Articles frequently describe specific station configurations, power sources, and operational challenges encountered during activations. Many entries include photographs of the operating environment and equipment, such as _portable antennas_ and transceivers, providing visual context to the operational narratives. The blog serves as a personal log of amateur radio adventures, sharing insights into effective portable operating techniques and station optimization for remote locations. Regular updates cover recent activations and related amateur radio topics.

"The QRP Adventures of VE3FI" is a captivating blog that chronicles the amateur radio experiences of Bill, VE3FI, over two decades. Holding Canadian Basic, 5-word CW, and Advanced licenses, Bill's main interests include DXing and QRP operations. The blog offers detailed accounts of his portable activations, such as a recent outing in March 2025, where he achieved impressive DX contacts on the 10-meter band using just 8 watts and a Hamstick antenna. Bill's engaging storytelling and practical insights make this blog a valuable resource for both seasoned and aspiring amateur radio enthusiasts.

This resource provides an in-depth look at Earth-Moon-Earth (EME) operating techniques specifically for the 432 MHz band and above. It outlines the differences in operational procedures between the 144 MHz and 432 MHz bands, emphasizing the importance of sequence lengths and scheduling. The initial calling period typically starts on the hour, with the eastern-most station calling first, which is crucial for effective communication. The document also discusses the challenges faced by operators, such as signal readability and the necessity of confirming exchanges. It highlights the significance of using a standardized procedure to enhance the likelihood of successful contacts. Additionally, it covers the use of signal reports and the importance of patience and clarity in communication, especially when dealing with weak signals. Overall, this guide serves as a valuable resource for amateur radio operators interested in improving their EME operations.

The Zeppelin antenna, a J-type design, is presented as a two-band HF dipole, offering independent operation on harmonically related frequencies. This resource details its electrical configuration, comprising a half-wave radiator end-fed by a quarter-wave matching section, and explores its historical evolution from early Zeppelin airship applications to modern amateur radio use. The article specifically examines how a Zepp antenna tuned to 28.4 MHz (10 meters) exhibits a harmonic relationship with 15.4 MHz (20 meters), noting a frequency ratio of approximately 1.84:1, which deviates from a perfect 2:1 due to factors like elevation, wire separation, velocity factor, and end-effect. Antenna modeling results, including SWR sweeps at 28.4 MHz (1.1 SWR) and 15.4 MHz (1.6 SWR), are provided through Graph 1 and Graph 2, illustrating the antenna's performance across these bands. Current distribution patterns for both the 28.4 MHz (second harmonic) and 15.4 MHz (first harmonic) operations are visually represented in Figure 2 and Figure 3, respectively. The author also includes a 4NEC2 model's "Symbol Conversion file" definitions and calculated #14 wire dimensions for achieving resonance at 28.4 MHz, with the antenna positioned at a height of 33 feet. The discussion further highlights the antenna's versatility, suggesting its potential as a single-band, center-fed, 15.4 MHz half-wave folded end dipole when fed at a specific low current point. This analysis provides practical insights into constructing and optimizing a multi-band Zepp antenna for HF operations, emphasizing its unique harmonic characteristics and physical compactness.