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This excel workbook addresses the issue of power loss in transmission lines with complex characteristic impedance ZoZo​. It illustrates the discrepancy between actual loss (0.35 dB) and matched line loss (0.6 dB) using a simplified example, highlighting potential software tool limitations. The RF Feedline Power-Loss Calculator provides accurate end-to-end loss assessments for both microwave and RF applications. This tool is suitable for engineers and students and is compatible with Windows versions of Excel 2016 or later, though it is not compatible with Macintosh systems.

Provides access to a robust DX cluster node, G6NHU-2, running DX Spider software, which facilitates real-time amateur radio contact spotting across HF bands. This service is engineered for high reliability and low latency, ensuring rapid dissemination of DX spots from a global network of interconnected nodes. It features multiple redundant links to prevent data loss and maintain continuous operation, even if individual connections drop. The cluster integrates directly with the Reverse Beacon Network (RBN), allowing users to enable or disable skimmer spots for specific modes like CW, RTTY, FT8, and FT4. It also offers an extensive one-year spot history, significantly longer than most other DX clusters, which typically retain only a month of data. The node supports various lookup commands for callsign information, beam headings, QSL routing, and FCC database lookups, enhancing operational efficiency for DXers and contesters. Additionally, it permits self-spotting, a feature increasingly relevant in modern contests, and provides detailed instructions for connecting popular logging software such as N1MM+, HamRadioDeluxe, MacLoggerDX, LOG4OM2, Logger32, and N3FJP's Amateur Contact Log.

Documents the operational planning for the **XX9W** DXpedition to Macao, a **DXCC** entity. This resource outlines the team composition, identifying 14 operators from various IARU regions, including EA1CJ, F2JD, and JH4RHF. It details the expedition's objective to activate Macao, officially the Macao Special Administrative Region of the People's Republic of China, emphasizing its distinct blend of Portuguese and Chinese cultures, historic architecture, and urban landscape. The site also provides information on how to support the DXpedition through donations, facilitating contributions via PayPal. Macao operates under the "one country, two systems" principle, with Chinese (Cantonese) and Portuguese as official languages, and a population exceeding 680,000. The content highlights the region's geographical location on the southern coast of China, across the Pearl River Delta from Hong Kong, and its historical background as a Portuguese colony.

EiBi-Tuner-v2 is an open-source macOS application designed to control amateur radio transceivers via the FLRIG interface, leveraging the EiBi-list for frequency management. This software provides a graphical user interface that emulates an older radio, allowing operators to tune their rigs based on the extensive EiBi database of broadcast stations and utility frequencies. The application is specifically compiled for macOS, offering a native experience for users of Apple's desktop operating system. The software's primary function is to simplify frequency selection and rig control by integrating the EiBi-list, which contains thousands of known frequencies, with FLRIG's robust transceiver control capabilities. This integration allows for rapid QSY to documented frequencies, potentially enhancing DXing and SWL activities by providing quick access to a vast array of signals. The open-source nature permits community contributions and modifications, ensuring adaptability and ongoing development for specific amateur radio operational needs.

The LY4A DX Reminder application monitors five distinct DX cluster sources—DXScape, DXSummit, DXHeat, PSK Reporter, and Reverse Beacon—to alert amateur radio operators when a specific call sign appears. It supports a wide range of bands from 160 meters to 70 centimeters, including 60m, 6m, 2m, and 70cm, accommodating **CW**, SSB, FT8, FT4, and RTTY modes. The software operates in the background, checking clusters at user-defined intervals of 1, 5, 10, or 30 minutes, and persists across device restarts. Alarm functionality is robust, activating even if the mobile device is silenced, by utilizing the alarm channel and illuminating the locked screen. On desktop platforms, notifications remain active in the system tray. Users can directly manage alarms—stopping, snoozing, or deleting them—from the notification interface, enhancing operational flexibility during DX pursuits. Available in 15 languages, including English, Italian, German, and Spanish, the application is provided free of charge and without advertisements. It offers optional donation support for continued development. Installation instructions are detailed for Android, Windows 10/11 (64-bit), and macOS 12+, addressing common system security prompts for unsigned applications.

Demonstrates _FreeDV RADE_, an open-source digital voice mode for HF, which combines machine learning with classical Digital Signal Processing (DSP) to achieve improved speech quality and spectral efficiency. Released in June 2025 by ARDC grantee FreeDV, RADE operates at Signal-to-Noise Ratios (SNRs) as low as -2 dB and occupies approximately 1.5 kHz of bandwidth, half that of a typical SSB signal, while transmitting about 8 kHz of voice audio. The mode also features an optimized Peak-to-Average Power Ratio (PAPR) for efficient power amplifier use, reducing heat and consumption. Users, such as _VK3TPM_, report significantly improved listening ease compared to analog modes, particularly in high HF noise environments, making it easier to conduct nets across various Australian states. The mode's integration into popular radios like the _FlexRadio 6000_ series allows direct operation without external computers. A C library for RADE is available, facilitating broader integration into other radios and SDR programs, with development continuing on FreeDV RADE v2 to further narrow bandwidth below 1 kHz.

Early 20th-century transatlantic wireless communication efforts involved distinct technical approaches by Reginald Fessenden and Guglielmo Marconi. Marconi's systems, operational until approximately 1912, primarily utilized _spark technology_ for wireless telegraphy, facilitating Morse code communication between ships and across oceans. His Poldhu station in December 1901 radiated signals in the MF band around 850 kHz, later evolving to 272 kHz in October 1902, and eventually 45 kHz by late 1907 with increasingly larger antenna structures like the pyramidal monopole and capacitive top-loaded arrays. Fessenden, conversely, focused on _continuous wave transmission_ for wireless telephony, recognizing its necessity for speech. His transatlantic experiments in 1906 employed synchronous rotary-spark-gap transmitters and 420-foot umbrella top-loaded antennas at Brant Rock, MA, and Machrihanish, Scotland, tuned to approximately 80 kHz. Fessenden later utilized the _Alexanderson HF alternator_ at 75 kHz by late 1906 for pure CW transmission, integrating a carbon microphone for amplitude modulation. Receiver technology also differed, with Marconi initially relying on untuned coherer-type detectors, later developing the magnetic detector in 1902, while Fessenden's CW approach necessitated more advanced detection methods.

The **590Ctrl** application provides a dedicated desktop control panel for the _Kenwood TS-590SG_ HF transceiver, specifically designed for macOS and Linux operating systems. Developed using the Qt 6 framework and C++, this software facilitates direct control of the radio via a USB connection, offering an alternative to the transceiver's front panel. The GitHub repository details its structure, including directories for documentation, resources, scripts, source code, and tests, indicating a well-organized development effort with a history of **41 commits**. Amateur radio operators utilizing the TS-590SG on macOS or Linux will find this tool particularly useful for integrating their radio into a computer-centric shack environment. It streamlines operations by allowing software-based adjustments and monitoring, which can be advantageous during contesting or DXing sessions where quick parameter changes are crucial. My own experience with similar control software confirms the efficiency gains, especially when managing multiple logging applications or digital mode interfaces simultaneously. The project's open-source nature also invites community contributions and further development, potentially expanding its feature set beyond basic control functions.

Examines the AOR AR-7030 communications receiver, detailing its technical specifications and operational characteristics. The resource describes its compact design, CNC machined aluminum cabinet, and a frequency range spanning 0-32 MHz. Key features include a ceramic metal cased 4 kHz AM filter, with typical bandwidths of 2.2 kHz, 4.0 kHz, 5.3 kHz, and 9.5 kHz, alongside 400 memory channels and multi-timer functionality. It emphasizes the receiver's high-quality components and a design philosophy focused on reliable performance without superfluous features, making it a dedicated tool for serious listeners. The review assesses the AR-7030's performance within its price class, particularly for **medium wave** and **shortwave** reception. It provides insights into how the receiver's design choices, such as its robust construction and specific filter options, translate into practical listening experiences. The analysis highlights its suitability for users prioritizing signal clarity and operational stability over extensive, complex features, offering a clear perspective on its utility for dedicated DXers and broadcast listeners.

This page provides a detailed review and setup guide for the K4 MacroMaster program, designed for Elecraft K4 and K4D radio users. The program allows users to easily program, test, and implement macro commands through Ethernet or Wifi connection. Users can create up to fifty user programmable macros in groups of 10, called Macro Clusters. The software includes an editor for creating, storing, and naming clusters by function, as well as a hint feature for quick reference. This resource is valuable for hams looking to streamline their radio operations with customized macro commands.

Presents the Mac TCI DX Cluster, a macOS application designed to streamline DX cluster activity for ham radio operators. GW3JVB developed this tool to provide a focused native Mac view of incoming spots, integrating local _RUMlogNG_ logbook context and selected TCI destinations. It allows users to save and connect to multiple Telnet cluster profiles simultaneously, merging feeds and filtering spots by bands, modes, and continents. The application features three independent outgoing TCI client slots for servers such as RigOne and Thetis, supporting spot forwarding and click-to-tune functionality. It reads local RUMlogNG logbooks for worked and needed checks without modification, offering callsign, DXCC entity, and continent checks. Watchlists, highlights, and optional alerts are included to emphasize important spots, helping operators find the next station worth working. Mac TCI DX Cluster complements existing station software, requiring macOS 14 or later on Apple silicon or Intel Macs. It is free to use, with downloads and release information available on GitHub, and optional donations are appreciated.

Dot & Dash is a macOS application for learning and practicing Morse code, providing an interactive environment for aspiring CW operators. The software features **twenty short chapters** that guide users from basic characters like E and T to the full alphabet, figures, punctuation, and common _prosigns_. Users learn by keying characters and words, with a daily five-minute review system to reinforce learning. The application allows users to compose messages, which the virtual machine then sends, or to key messages themselves and observe real-time decoding. It supports various input methods, including holding the Space bar, using a virtual knob, or connecting a USB key/keyer that emulates keyboard input. Operators can adjust sending speeds from **5 to 40 WPM** and apply _Farnsworth spacing_. Further capabilities include converting Morse code to text and vice-versa, and a "Type Anywhere" feature that enables keying Morse directly into other Mac applications. The software operates offline and offers a 24-hour free trial before requiring a one-time purchase for full functionality.