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A presentation of the Yagi Antennas, and other interesting tid-bits by Brian Mileshosky. The document provides an in-depth exploration of the Yagi-Uda antenna, detailing its historical development, design principles, and performance characteristics. Originally described in the 1920s, the Yagi antenna features a driven element and parasitic elements, including reflectors and directors, which collectively determine its behavior. The document highlights how element lengths, diameters, and spacing influence gain, impedance, and directivity. It also discusses the antenna's reciprocal nature and presents data on typical gain values for various element configurations. Additionally, the text covers practical considerations, such as the construction of a "Tape Measure Yagi" for amateur use, and touches on related antenna types like dipoles and their application in Near Vertical Incident Skywave (NVIS) communication.

A december 2003 QST article to Build a condenser microphone that will perform like the costly commercial units by KT4QW

When I tell friends that I enjoy amateur radio contesting, their reaction is usually a quizzical stare. "What's that?" It is hard to explain in the span of a cocktail conversation, so here is the answer.

A Chaotic Collection of Keys, Paddles, and Bugs

A distributed capacity coaxial dipole antenna. The antenna is very broadbanded with a very flat swr on all band when setup of the antenna is done at the proper lenght and height.

The ADIF Processor is an online application that visualizes amateur radio contacts from an ADIF log file using Google Earth. SOTA CSV log files can also be used. As well as allowing you to view and explore your contacts in Google Earth, you will be able to see a Markdown or text table of contacts, use the output ADIF file which contains QRZ.com data, accurate contact distances and fields populated from comments in the input file. Print QSL labels. One of the benefits of using the ADIF Processor before uploading/storing your ADIF file is detecting errors in callsigns and activity references (e.g. POTA or SOTA references).

A free PDF from NASA about cubesat. Basic Concepts and Processes for First-Time CubeSat Developers. A great introduction document dedicated to Cubseat developers.

An interesting presentation of a real multiband Fan Dipole antenna, optimized for better DX operation performances, considering the terrain, position, DX destination path and other influencing factors

A homemade band pass filter for the 30 meter band based on the original VE7BPO design

A multiband vertical antenna for HF bands with elevated ground radials slant down at 45 degrees and acting also as guy wires.

30 meters beacon from UK. QRSS is a method of sending very slow morse code.

An open design exercise in interface archaeology, that decodes the input from a classic Morse key to send twitter messages

Constructing a compact directional antenna for the 17-meter band, this resource details the build process for a Moxon rectangle, a two-element Yagi variant with folded-back elements. It covers the antenna's evolution from the _VK2ABQ beam_ and provides specific dimensions for a version built using fishing pole whips. The content includes a discussion of the antenna's radiation pattern, feedpoint impedance, and its inherent front-to-back ratio, which is often superior to a standard two-element Yagi. Practical considerations for element spacing and material choices are also addressed, alongside a visual representation of the antenna's physical layout. Performance data presented includes a comparison showing the Moxon rectangle's **2.5 dB gain** over a half-wave dipole and a front-to-back ratio of **20 dB**. The resource also touches upon the antenna's relatively wide bandwidth for a two-element beam and its suitability for portable operations due to its compact footprint. It offers insights into optimizing the design for specific operating conditions and discusses the advantages of its lower take-off angle compared to omnidirectional wire antennas, making it effective for DX contacts on the 17-meter band.

10MHz WSPR and QRSS Transmitter Project

How to make proper maintenance of your antenna. Fighting Antenna Corrosion is a QST article published in 1993 that helps on antenna maintenance works

How do two-wire reversible direction Beverages work, an excellent document that explains fundamentals of beverage antennas. This article details the design and performance of a reversible beverage antenna. Leveraging orthogonality between common mode and differential mode currents on a 2-wire line, this antenna facilitates independent reception from both ends. While common mode signals arrive and are summed on a transformer's secondary for common mode reception, differential mode signals induce anti-phase currents, providing individual reception. Various measurements explore impedance, transmission loss, and F/B ratio, highlighting the antenna's effectiveness and areas for improvement. Notably, increasing the antenna's height significantly improved performance.

The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.

Keyclicks and NB modifications for the Yaesu FT-1000MP Mark-V HF transceiver

Three Yagi antennas for the six meters band by 9A7PJT. Include a 4 element yagi, a custom design 4 element, and a 5 element yagi with antennas pictures and design.

A custom manual for the Yaesu FT 450 owners, tha includes system controls, factory reset procedure, procedural uses, memory management, programming and many more

T2FD is a 600-900 ohms folded dipole, terminated with resistor. Feed impedance is coupled with 50/600 ohms voltage balun. It is a wide band antenna with rather low SWR over the full designed frequency range: antenna tuner is seldom needed.

A 70 MHz QRP transverter project

Homebrewing portable antennas for field day operations

Facilitates logging of amateur radio contacts directly within a web browser, enabling seamless operation across various devices including Windows, macOS, Linux, iOS, and Android. This web-based application stores all log data securely in the cloud, providing accessibility from any internet-connected location. It supports importing existing log data via CSV files, with future plans for _ADIF_ file import, and offers a robust QSL card generation feature, producing print-ready PDF files in standard 148mm x 100mm dimensions. The platform integrates with Japanese government databases to automatically populate callsign-related information such as station location and license issue dates, streamlining data entry. It also assists with JCC/JCG searches for accurate QTH logging. The service leverages SSL encryption for all communications and benefits from security oversight by certified information security professionals. Users can register using email/password or existing Facebook/Google accounts, and the beta version is currently available for free. The system has processed over **5,297,881** logs, with **28,369** logs recorded in the past 24 hours.

Exploring these mysterious transmissions and how their strong following has created a niche in the community. Free article in PDF Format from QST November 2019

Receiver performance test of the Icom IC-7610 transceiver done by Rob Sherwood

DIXPRS is an APRS Internet Gateway and Digipeater software for HAM radio use. It is designed to be portable and platform independent as much as possible. To reach this goal it is written in Python with minimal dependency considering older versions of operating systems and Python.

HF VHF UHF antenna ideas to be used for field days. All antennas are quick to set up and take down and offer proven performance and flexibility. Presentation offered by Mahoning Country ARES

A different implementation of the G7FEK HF multiband antenna with some adjustments and modifications

MBU Cluster is simple android application for ham radio operators to view live the spots on mobile device. All the spots are refreshing every 60 seconds.

This application allows Ham Radio Operator to browse and search his LoTW QSL confirmations on his handheld device, and receive notifications when new QSL confirmations appear on Logbook of the World.

A simple drawing schematic of a portable field dipole for 14 MHz with dimensions in meters and instruction for setting up the antenna and to store the radial for easy transportation

This project is a Software Defined Radio Receiver. It has a frequency range of 24MHz 1.2GHz. It can demodulate AM, FM, USB, LSB with selectable bandwidths of 600, 2400, 2800, 3200 and 6400Hz. Using a simple RTL-SDR Dongle and Raspberry Pi 3 computer using GNU RADIO

A selection of speakers or headphones for use with amateur radio equipment. Includes an interesting paragraph comparing Dynamic and Electret Condenser Microphones, but also about audio Equalization.

A Microvert antenna by KD5RVX based on the original microvert concept by DL7PE. PDF includes a 20 foot portable PVC tower project

This article is about a 4 element yagi VHF antenna designed to be easy to be assembled and suited for portable operations

If you want to design vertical antennas you can find all theory and formulas used to model a vertical aerial calculating capacitance, reactance, building the inductor and calculating resistances. Includes an excel spreadsheet to calculate efficiency.

A nice review of the Acom 1000 HF and 6 meter RFpower amplifier by Acom in Dutch and with online google translation available. Includes pictures and notes of the popular amplifier by Acom.

Receiver performance review of the Kenwood TS-890S HF,50MHz,70MHz amateur radio transceiver by Sherwood Engineering

AudioXplorer is a sound analyzer software designed for Mac OSX, provide a real-time analysis window where you can visualize the sound spectrum and sonogram

A 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

An unusual Titan DX antenna seutp, done without the standard counterpoise. This document is not an official manual, but rather a personal note to record the antenna setup with the custom wire counterpoise.

A Programming-Free Automatic Arduino Antenna Switch project published on NCJ

Presentation about Practical Antenna Modeling Using the NEC Codes with examples of HF wire antennas and 4NEC2. How to define and edit the models, Running the simulations, Work some examples, Variables usage, Deal with Feed Lines and ground

The Lakeshore Repeater Association (KR9RK) operates a **VHF** 2-meter repeater on 147.270 MHz, utilizing a +600 kHz offset and a 100 Hz PL tone, serving the Raymond, Wisconsin area. The organization provides access to monthly newsletters, with recent editions including March 2026, February 2026, and January 2026, detailing club activities and operational updates. A Google Docs link is provided for newsletters with functional embedded links, addressing issues with PDF versions. The association's Megacycle Group is actively constructing a **DX Contest** level HF network, designed for remote accessibility. This initiative aims to provide members with a competitive edge in global DX hunts by enabling worldwide access to the station's radios. Additionally, the Lakeshore Radio Association is commemorating its 50th anniversary with a special event station, K5O, inviting all members to participate in on-air operations.

Pictures, design plan and description of a 5 element yagi antenna for the 4 meters band by 9A7PJT

European version of the ICOM IC-7610 leaflet in A4 Format PDF File

LDG z-100 autotuner review by GW6ITJ

An interesting presetnation full of usefull tricks to correctly design and build 23 cm Yagi using simple tools. The basic design of the antenna presented in this document is taken from the original DL6WU Yagi Design published in 1982

Six meters is a great band for home built Yagis. The elements are reasonably small, but not so small that building tolerances are critical. With careful construction and detailed instructions, it is certainly feasible to build no-tune Yagis up to 432 MHz.