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This article describes a DIY RF field strength meter project inspired by VK3YE's "The Squeakie" design. The device, built around a 555 timer IC and a 1N4148 diode, converts RF signal strength into audible tones with proportional pitch. The author enhanced the original design by adding volume control, LED indication, and digital readout capabilities using an Arduino Nano and LCD display. The completed project functions as a versatile RF detection tool, suitable for antenna testing and fox hunting, while offering multiple output methods: audio, visual, and digital measurement display.

This resource details a practical RFI fix for the Yaesu MH-59 microphone, specifically addressing interference encountered during Field Day 2004 operations. The modification involves installing a small toroid core onto the microphone's internal cable connector. The author, AE7Q, describes the process: purchasing a ½" outer diameter, ¼" inner diameter toroid core from a surplus store, opening the MH-59, unplugging the cable connector from the circuit board, looping the cable through the toroid, and then reassembling the microphone. This fix is intended for amateur radio operators experiencing RFI with their Yaesu MH-59 microphone, particularly in environments with strong RF fields like those found at Field Day events. The page also directs users to the AE7Q message board for questions and comments.

The Elecraft KX2 and AX1 portable field kit is reviewed for its efficacy in rapid Parks On The Air (POTA) activations, focusing on a specific outing by _K4SWL_. The resource details the setup, including the _Elecraft KX2_ transceiver, _AX1_ antenna with a 3D-printed bipod, _Begali Adventure Dual_ paddles, and various accessories like the Windcamp X2 Side Rails and Tufteln KX2 Protective Cover. It outlines the practical considerations for a quick deployment, such as avoiding tree-thrown lines due to back pain, and emphasizes the minimal setup time required to get on the air. The activation described involved 11 contacts logged on 20 meters within 14 minutes, demonstrating the system's efficiency for "grab-and-go" operations. A QSO map visualizes the contact locations, and an unedited video documents the entire activation process. The review highlights the kit's reliability and compact nature, making it suitable for urban parks or situations where rapid deployment and minimal footprint are essential. The author expresses appreciation for the kit's tidy organization and consistent performance over several years of portable use.

Operating an **Echolink** gateway on the 4-meter band presents unique opportunities for extending VHF communications, as demonstrated by the EI4FMG node. Situated at Fieldstown, Monasterboice, this gateway provides coverage across a significant portion of Ireland's east coast, leveraging a Tait TM8100 radio and an EI4JR Echolink interface logic. My own experience with similar setups confirms the importance of strategic site selection for maximizing reach, particularly with a 122-meter elevation above sea level. Access to the EI4FMG gateway, identified by node 57006, requires a **CTCSS** tone of 88.5 Hz, a standard practice for managing access and minimizing interference on shared frequencies. The system transmits with 15 watts of power and utilizes a Sigma CAT70 @5MAGL antenna, a configuration well-suited for regional VHF coverage. The gateway also features an auto-ID every 8 minutes, ensuring compliance and clear station identification. Users can interact with the gateway using various DTMF commands, allowing for connections to specific nodes, random repeater/link or conference nodes, and managing disconnections. These functionalities streamline the process of linking into the broader Echolink network, enabling local VHF operators to communicate globally through the internet backbone.

PD0G recounts the journey of building a 70cm Swiss Quad antenna, inspired by a vintage 2-meter version acquired for study. The author meticulously examines the original design, noting its distinctive curved metal elements and mechanical structure, which deviates significantly from traditional cubical quads requiring spreaders and wire. Historical context is provided, tracing the Swiss Quad's origins to R.A. Baumgartner (HB9CV) and its appearance in publications like the RSGB Bulletin in 1964 and QST in 1967, while also distinguishing it from other HB9CV designs. The project details the scaling process for 70cm, utilizing a calculation chart from F6ITV for initial dimensions and an existing MMANA-GAL model for 6 meters, scaled down to 433 MHz. Emphasis is placed on the critical gamma-match adjustment, with custom-machined POM parts for precise positioning and electrical isolation. Initial construction with 5mm aluminum elements and a 15mm boom led to practical challenges in bending and achieving target dimensions, necessitating adjustable element sections to fine-tune resonance. Measurements with a CAA-500 and SV4401A VNA confirmed a good match at 432.500 MHz with an SWR of 1.022 and LogMag of -39.46 dB. The author highlights that while a good SWR is achieved, further field testing is required to assess actual gain, directivity, and front-to-back ratio, especially when comparing single versus double element configurations. The article concludes by advocating for revisiting older, less common antenna designs, emphasizing the learning and satisfaction derived from hands-on experimentation.