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Have you ever thought of setting up a portable HF station for an activity ?

Adding 17 meter band to Mosley TA-33M yagi antenna

Getting started on RTTY contesting. A PDF by ED Muns, presented at CTU conterst university, about amateur radio RTTY Contesting

Marshall G. Emm, N1FN, meticulously examines iambic keying, dissecting its historical introduction in the late 1950s with transistorized electronic keyers and its purported advantages. The resource defines keying systems, electronic keyers, and various paddle types, including single-lever and dual-lever paddles, clarifying the distinction between iambic keyers and the iambic sending technique itself. It details the two main types of squeeze keying: true squeeze for alternating dot-dash strings and character insertion for specific elements within a character. N1FN critically evaluates the actual efficiency gains of iambic keying, referencing Chuck Adams, K7QO's, keystroke analysis. While a straight key to bug transition yields a 34.1% reduction and a bug to non-iambic keyer offers 16.1%, iambic keying provides only an 11% theoretical improvement. However, considering typical QSO text and Morse code's inherent optimization for common letters, the practical efficiency gain is estimated at a modest 4-6%. The article also highlights how iambic keying's reliance on precise timing gates can impose a speed limit, making it less effective above 40 WPM, where many operators revert to non-iambic methods or single-lever paddles.

This is a QST Article published in January 1982 by W1FB D. Demaw and HH Beverage and is a complete review of the original article published in 1922, which updates and reivew the beverage antenna theory and developlment, explaining the antenna design of transformers and gives accurate reports on antenna general performance.

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

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

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?

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 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.

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

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.

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

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

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

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.

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.

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

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

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

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

Homebrewing portable antennas for field day operations

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

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

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 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.

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 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

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.

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.

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

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

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.

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

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

A homemade 23 cm transverter project with several building steps and pictures

The purpose of this book is to provide a common source for WIRES-X, gather information from manuals, experiences from the Amateur Radio Community, and the best practices from both the Amateur Radio Community and the Bakken Amateur Radio Society. To provide a platform for learning, experimentation, and advancement of Amateur Radio skills and art. A platform of Discovery and to have FUN. To encourage networking, sharing, and exchange of interesting technical information of WIRES X, where people are encouraged to help each other out.

Simple steps you can take to solve most problems caused by station equipment

Icom IC 756 Pro 3 English User Manual in a PDF file

A Comparison of most popular Amateur Radio Digital Voice Systems DMR D-Star System Fusion presented by W9HPX Roland at the Charlotte Digital Radio Group in a comprehensive article about Digital Voice

This article describes the development of two tunable antennas each consisting of three interconnected small loops and capable of providing excellent DX performance. The aerials are home-constructed, and located in a very small garden with a minimum of visual impact on the neighbours and are low enough in height to avoid the attention of UK planning authorities.

How to home made antenna traps with material you can easily find, and how to properly tune it.

Homemade LC Bandpass Filters for 20M, 30M, 40M In multi-station environments like special events, field day, portable operating, is very important to protect receivers from excessively strong signals. Bandpass filters help to protect your transceivers.