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Hone your Morse code skills with this entry-level project. Article includes the full schematic of the CW Trainer, describes the sketch and how to operate the morse code trainer.

Developing a protection plan against lightning

There are many designs for building preamps each with their own advantages and disvantages. In this PDF Article author reviews several different types.

Design and build a 6 meter 2-element Moxon antenna mostly from available aluminum tubing and angle stock.

The author who works successfully via EME on this band wants to describe his own yagi design and give some of hints for the construction. by Heinrich F. Reckemeyer, DJ9YW

This document is a must read for anyone considering building a good low cost HF multi-band antenna system. The author combine in this document four important ingredients to produce simple but effective antenna system, like antennas of non resonant length, line attenuation, the transmatch and the balun

About Coax Traps, NC4FB examine the operation of coax traps through modeling.

High Speed Multimedia Radio Introduction by ARRL Working Group Chairman. Report of the High Speed Multimedia (HSMM) Working Group ARRL Board of Directors 2006 Annual Meeting January 22, 2004

FLMSG is a simple forms management editor for the amateur radio supported standard message formats. Form data can be transferred between computers either using standard internet email or via radio frequency broadcasts typically made by an amateur radio operator on your behalf.

A 160W linear amplifier for 4 meters band based on GI0GDP

Cushcraft XM240 transformation into a Moxon antenna by W6NL

By by Larry Wolfgang WR1B in QST Archives at ARRL

This is a schematic drawing of a project for the construction of a portable mast that can easily be made with PVC pipes.

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

A look behind the scenes, learn how the ARRL laboratory evaluates new products, and what all those numbers mean to you by WA1SVF

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?

Presentation about finding, restoring, updating and operating vintage Ham Radio by K4QKY and Bill Call, KJ4W

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

Gnerate morse code at various speeds and with lots of different types of content, everything from individual letters up to a full QSO.

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 dual band portable inverted V antenna for 80 and 40 meters band with dimensions for other bands and several assembling instruction

This is perhaps the most important parameter in many oscillators and it deserves an in-depth discussion on what it is, how it affects a system and how it can be minimised in an oscillator design.

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

Solar Flux, Geomagnetic Activity indexes and interpreting their relation

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

JT44: New Digital Mode for Weak Signals

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.

Presents a concise guide for Amateur Radio operators participating in Jamboree-on-the-Air (JOTA), an annual event connecting approximately 500,000 Scouts and Guides worldwide via ham radio. The resource details how to initiate a voice contact, including the use of "CQ Jamboree JOTA" and proper signal reporting with the RST system. It also outlines the typical exchange information, such as name, QTH, Scout rank, and age, encouraging participants to practice their responses. Authored by Bill Wetherill, N2WG, the brochure provides a practical phonetics chart and a comprehensive Morse code dictionary, including punctuation and prosigns like AR and SK. It clarifies rules for third-party operation under the direct supervision of a licensed operator, noting restrictions on international contacts without specific government agreements. Additionally, the guide lists recommended World Scout Frequencies for SSB and CW across 80, 40, 20, 17, 15, 12, and 10 meters, emphasizing courteous operating procedures. It includes a section on common Q-signals like QRM, QRN, and QSL, alongside the Amateur's Code, which stresses considerate, loyal, progressive, friendly, balanced, and patriotic conduct.

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.