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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 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.

Introduction to WSPR beacons. Article describe WSPR2 and WSPR15 beaconing mode and include a frequency reference table for both WSPR modes

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.

Technical supplement manual of the Yaesu FT-8800R in english

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

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 can the current "flowing" out of the top of a mobile loading coil be greater than the current "flowing" into the bottom of the coil?

Manual of the BD-35 Dual Band VHF UHF RF power amplifier by Mirage Amp

The TransWorld Antennas TW4040 The Adventurer Monobander™ is a portable HF antenna designed for rapid deployment in field operations, including **SOTA** and **POTA** activations. This manual details the antenna's assembly, tuning procedures, and operational guidelines for optimal performance on the 40-meter band. It outlines the specific components, such as the telescoping whip and base unit, required for proper setup. Instructions cover mast erection, radial wire deployment, and impedance matching to achieve a low **VSWR** across the designated frequency segment. The document also provides guidance on antenna orientation and environmental considerations for portable use. It specifies the antenna's power handling capabilities and physical dimensions when fully deployed and collapsed for transport.

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

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.

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 Chaotic Collection of Keys, Paddles, and Bugs

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

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.

A 70 MHz QRP transverter project

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

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.

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.

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

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

10MHz WSPR and QRSS Transmitter Project

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

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.

The _Letter Post Regulations_ article RL 128 defines specific dimensional requirements for address placement on envelopes, crucial for efficient postal processing. The addressee's address area must be positioned at least **15 mm** from the right and bottom edges, and at least **40 mm** (with a 2 mm tolerance) from the top edge, extending no more than 140 mm from the right-hand edge. These precise measurements ensure rapid optical reading and facilitate manual sorting and delivery by postal services. Adherence to these Universal Postal Union (UPU) standards prevents interference with indexing, coding, and address detection areas, which must remain blank. While individual countries may adapt these values, they must maintain a minimum address area width of 74 mm. Proper placement avoids extraneous markings to the right, below, or within a 15 mm wide area to the left of the address, extending from the first line to the bottom edge, and a 15 mm high by 140 mm long area from the bottom-right corner.

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

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

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

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

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.

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

This home made antenna provides around 10.5dBd gain on 70cm, and 6.5dBd gain on 2m, which is more than adequate to work the FM satellites with a handheld dual band radio

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

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.

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

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

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 collection of audio amplifier projects by N1HFX

N1HFX project to improve PL tone encoder providing a more stable frequency

A dipole can be broadbanded by a number of techniques including by matching with resonant sections of transmission feed lines.

Homebrewing portable antennas for field day operations

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.

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.

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

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.

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

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.

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.