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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.

Examines the Sangean ATS-505 portable receiver, a unit introduced in March 2000, providing an in-depth analysis of its capabilities. The review details critical specifications such as its 6 Volt DC power requirement, utilizing 4 AA batteries, and its physical dimensions of 128 x 214 x 39 mm, weighing 840 g without power cells. Frequency coverage spans **LW** from 153-279 kHz, **MW** from 520-1710 kHz, **SW** from 1711-29999 kHz, and FM from 87.5-108 MHz, making it a versatile listener for various broadcast types. Key features highlighted include a backlit display for low-light operation, 45 memory presets for quick access to favorite stations, and the inclusion of Single Sideband (SSB) mode, which is crucial for serious shortwave listening and utility monitoring. The review also draws technical comparisons with other Sangean models, specifically the ATS-404 and ATS-909, pointing out differences in band coverage and operational features. This independent assessment offers practical insights into the ATS-505's performance, helping enthusiasts understand its place within the portable receiver market.

Over 20 news items and announcements are regularly featured on KFPortal, a Polish-language amateur radio community platform. It serves as a central hub for both licensed operators and shortwave listeners, providing a robust platform for discussion through its forums, a marketplace for equipment classifieds, and a source for current radio news. The site also hosts a searchable library of manuals, which is particularly useful for troubleshooting older gear, alongside various operator tools and Morse code training resources. Beyond its core community features, KFPortal offers a dual-language interface, supporting both Polish and English users. This accessibility broadens its reach, allowing a wider audience to engage with content, including updates from organizations like _AMSAT_ concerning SSTV transmissions from the _International Space Station_ and coordination efforts for projects such as UNNE-1B. The portal regularly features news items, such as the recognition of Murray Niman with the Roy Stevens Memorial Trophy and reports from significant events like the 27th IARU Region 1 Conference in Vienna.

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.

Define the SWL contest 2026 as an event for monitoring a variety of languages on _medium wave_ (MW) and _shortwave_ (SW) AM radio stations. Participants can utilize either traditional radio receivers or _WEB SDR_ platforms to log their findings. The contest encourages the use of both analog and digital methods to maximize the diversity of languages captured. The contest rules specify that entries must include detailed logs of the stations received, including frequency, time, and language identified. Logs should be submitted in a standardized format to ensure consistency and accuracy in judging. The use of WEB SDR is particularly highlighted for its ability to access distant stations that may not be reachable with local equipment. The contest is open to all SWL enthusiasts worldwide, with a focus on European WEB SDR access. The event aims to foster a deeper understanding of global broadcasting patterns and linguistic diversity. Participants are encouraged to explore various bands within the MW and SW spectrum, enhancing their skills in signal identification and language recognition. The contest offers a unique opportunity to engage with the global SWL community and share insights into the art of listening.

Demonstrates the conversion of an _Elecraft K2_ QRP HF transceiver to serve as a 2-meter Intermediate Frequency (IF) rig for microwave transverters, addressing the obsolescence of older _Yaesu FT-290R_ units. The project integrates a _DEMI 144-28DC_ transverter board, configured for a 28 MHz IF, and details the necessary modifications to the K2, including the installation of the K160M module for a separate receive-only antenna input and the KSB2 SSB module for voice operation. The modified K2 provides a stable 1-watt output for the 2m IF, utilizing the QRP antenna jack for transmit and the K160M input for receive, with a custom PTT control circuit. The article outlines the physical integration and electrical interfacing, including the design of an internal attenuator for the 28 MHz IF output and a control circuit for the 144 MHz interface. It also covers the construction of a medium power amplifier using an _MGA-31389 MMIC_ to boost the 2m output to 100 mW, matching the original FT-290R performance. Performance measurements for the amplifier, including output power versus input power and gain versus frequency, are presented. The project culminates in a fully integrated solution, with schematics and photos illustrating the internal wiring and external connectors. The modified K2, dubbed the "K290R," was successfully deployed in the 2017 _ARRL 10 GHz and Up Contest_ with a _Kuhne 10 GHz_ transverter, demonstrating reliable operation for CW and SSB modes.

The 9 dB gain 70cm collinear antenna project details the construction of an 8-element array using RG58/U coaxial cable, designed for the 444 MHz band. Each half-wavelength section of RG58/U is precisely calculated, accounting for a velocity factor of 0.66, ensuring optimal resonance and performance. The design incorporates a quarter-wave wire element at the top and a quarter-wave aluminum or copper tube at the bottom, with specific length calculations provided for each component. Construction involves careful cutting and soldering of the coax elements, exposing the center conductor and braid, and tinning the braid for robust connections. The feed point connection to the main RG58/U coax is also thoroughly described, ensuring proper impedance matching for the UHF band. Encased in PVC pipe for weather protection, this homebrew antenna offers a cost-effective solution for amateur radio operators seeking a reliable UHF antenna. The article includes step-by-step instructions, making it accessible for those interested in building their own antennas.

Jamboree on the Air (JOTA) is an annual Scouting event held on the third full weekend of October, coinciding with Jamboree on the Internet (JOTI). This global event facilitates communication among Scouts worldwide using amateur radio, enabling participants to exchange Scouting experiences and ideas over short-wave signals. It serves as an educational platform for Scouts to learn about wireless radio techniques and basic electronics. Participation necessitates the support of at least one licensed amateur radio operator or a local amateur radio club. National amateur radio organizations can assist in locating local operators. Licensed operators, having passed technical examinations, may host Scouts at their stations, transport equipment to Scout headquarters, or establish temporary stations in various locations. Depending on national regulations, Scouts may speak directly over the air, or special permission might be required, with the licensed operator making contacts on their behalf. Operators are encouraged to familiarize themselves with Scouting principles to facilitate more informative and engaging exchanges.