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DecoDXLog is a station logbook application for Windows, designed to integrate seamlessly with the _Decodium_ family of software, as well as _WSJT-X_ and JTDX, by receiving QSOs via UDP. It operates around a local SQLite file, providing automatic callbook lookups from QRZ.com XML or HamQTH to complete log entries with name, QTH, and locator data. The software tracks 15 different awards, including DXCC, WAZ, WAS, WPX, IOTA, POTA, and SOTA, calculating progress in real-time and allowing confirmation via LoTW, paper cards, or eQSL. It also features comprehensive statistics, a world map displaying worked locators and cluster spots, and a built-in DX Cluster client that aggregates data from DX Spider/CC Cluster, Reverse Beacon Network, HamAlert, and POTA activations, providing alerts for new DXCC, band, or mode. The application includes a CW keyer/decoder, a contest mode with real-time scoring and Cabrillo export, and robust QSL management for LoTW, QRZ Logbook, eQSL, and Club Log. An optional DecoDXLog Cloud feature enables synchronization of QSOs, station profiles, and settings across multiple devices, ensuring a consistent operating environment. The software is open-source under the GPL-3.0 license, developed by IU8LMC and contributors, and supports lossless ADIF import/export, making it compatible with existing logs. It also integrates with _DecoRotor_ for antenna control, allowing operators to point their antenna directly from the logbook interface.

Exploring digital radio modes, the author rethinks how to adjust transmit and receive levels in WSJT-X. Despite effective communication using Yaesu's settings, a new procedure aims for better performance. For RX, set audio device levels to 100%, disable AGC, and adjust RF gain. For TX, enable "Remember power settings" and adjust power output to avoid ALC engagement. This method ensures reliable communication without signal degradation, enhancing dynamic range and minimizing noise.

The Olivia digital mode, a **Multi-Frequency Shift Keying (MFSK)** radioteletype protocol, is specifically engineered for robust communication under difficult propagation conditions on shortwave radio bands from 3 MHz to 30 MHz. Developed by Pawel Jalocha in 2003, Olivia signals can be decoded even when the noise amplitude exceeds the digital signal by over ten times, making it highly effective for transmitting ASCII characters across noisy channels with significant fading and propagation phasing. Early on-the-air tests by Fred OH/DK4ZC and Les VK2DSG on the Europe-Australia 20-meter path demonstrated intercontinental contacts with as little as one-watt RF power under favorable conditions. Common Olivia modes are designated as X/Y, where X represents the number of tones and Y is the bandwidth in Hertz, with examples including 8/250, 16/500, and 32/1000. The resource clarifies that Olivia, unlike some other digital modes, produces a constant envelope, allowing RF power amplifiers to achieve greater conversion efficiencies and making it less prone to non-linearity. Operators are advised that **Automatic Level Control (ALC)** can be set higher than no meter movement for MFSK modulation, as long as it's not driven past its high limit, contrary to common misinformation about other digital modes. The Olivia community encourages voluntary channelization on suggested calling frequencies, such as 14.0725 MHz for 8/250, to facilitate initial contacts, especially for signals below the noise floor. The Olivia Digital DXers Club provides links to Groups.io, Facebook, and Discord for community engagement and offers details on QSO parties.

The Open NEC2 Viewer for Android provides a mobile platform for **NEC2** antenna modeling, enabling users to visualize and analyze antenna designs directly on their devices. It integrates the robust NEC2 computational library, leveraging the Method of Moments for full-wave electromagnetic analysis, and utilizes the Google Filament renderer for interactive 3D visualization of antenna structures, segmentation, and wireframes. The application facilitates the calculation of geometric parameters and antenna characteristics across specified frequency ranges. Key functionalities include parametric analysis, offering real-time computation of **radiation patterns** (RP), antenna gain, Voltage Standing Wave Ratio (VSWR), and input impedance. Users can configure flexible calculation settings to control scan step, frequency range, and various control cards, allowing for detailed electromagnetic analysis tailored to specific design requirements. Designed for radio engineers, antenna developers, radio amateurs, and students, the app is distributed as open-source software under the GNU General Public License v3.0. It provides a portable and accessible tool for electromagnetic modeling, making advanced antenna analysis capabilities available on Android devices.