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Complete collection of the four main parts of this excellet research on modelling and designing half wave dipole antennas for 40 meters band, covering all aspects beginning from full wave length antennas, to shortened, loaded and reshaped dipoles

About experiments and measurements on loading coils using net standing wave current

A complete guide for newcomers edited by the Radio Amateur Society of Australia Inc. This free PDF includes several basic articles for new hams, with particular reference to Australian regulations, but is however a good guide for those who are aproaching the hobby worldwide.

An article edited and published by Michael Mandeville on correlation of sunspot peaks and global events, like recessions or human conflicts. This document include solar cycle charts since Solar Cycle 1749-1751

Extension of the Kenwood TS-590S Programmable Function by CT7AEZ

Schematic of a fast charger for Gel Cell batteries

A dual band dipole antenna for 40 and 80 meters band. Total lenght of 26 meters, foreseen two coils at aprox 11 meters distance from center feed.

How to improve your transmitting antennas for very low solar activity periods, vertically polarized 160 meter antennas, horizontally polarized 80 to 10 meter antennas, single or stacked yagis, multi-tower stations

An interesting article on pedestrian portable HF DXing

Adding a Software Defined Radio to an SO2R station

Main High Frequency Antennas from the 2009 LARC FARL Field Day, Ford Amateur Radio League. A document comparing antenna performances and flexibility among a G5RV an Carolina Windom and a Cushcraft R7 vertical antenna.

Android Echolink client to connect to the echo link network

Using Chokes and Traps: how to make them, how they work.

Consider installing a stealth vertical loop antenna if you live in a place with no antenna restrictions. Full wave loop wire antennas allow you to be on the air without installing evidente external aerials.

An operating guide for the com IC-2720H VHF/UHF Radio, includes Turning the power On or Off, Selecting the Output Power, Activating Memory Mode, Operating in Memory Mode

If you like building good antennas, this one is for you. The J-pole is a slim, omnidirectional, half-wave antenna fed at the end through a quarter-wave shorted transmission line. Its predecessor is the famous Zepp antenna developed for the Zeppelin airship.

GW6ITJ articles on morse code, learning techniques, clubs and organizations and a custom learning software.

Amateur radio map of Italy with WW locators, provinces abbreviations and Call sign Prefixes, in a A3 size PDF file free to download, made available by IU3KJL Davide

Dubus article about DL6WU long yagi antennas for 23 cm band Article is both in german and english. Yagi antennas are valid alternative to dishes for troposcatter operations. This article explains design and mechanical data for 1296 MHz Yagi Antennas

This EXCEL Program Worksheet calculates the common-mode impedance of a 1:1 Guanella (current) balun which is placed at the feed point of a balanced antenna system fed via coax.

A low cost, low power microwave transverter so that you can operate easily on 70cm band even with a HF or VHF transceiver

Read more about the purpose, policies, and procedures of The National Traffic System in this 48 pages PDF File

Roach pole vertical antenna for 40 and 30 meters band featuring good performance on short skips contacts compared to wire dipole

This antenna is a vertical loop antenna mounted on a 8 meters high grounded mast with an input impedance of 50 Ohms without a matching device

In this article, author examine stresses placed on common-mode chokes (aka baluns) as hams use/abuse them, examine the efficiency of simple dipole multi- band antennas and their feed systems. Stressing a Balun.

This article is about a home made project of a whip antenna for 2 meters band. Includes lenght of whip for all frequencies from 140 MHz to 151 MHz both in mm and inches

Adapted from a similar project by NA4IT. Made with one quarter wave 2 meter radiating element pointing upward and it is surrounded by four 70 cm elements.

An inverted V Dipole antenna for HF bands, working on 10 20 40 and 80 meters band. PDF Presentation

AMSAT is a worldwide group of Amateur Radio Operators who share a common interest in building, launching and communicating with each other through non-commercial Amateur Radio satellites.

Display your current Maidenhead locator with 10 digit precision. It also computes bearing and distance to a set of target locations using locator or latitude / longitude. Useful to align antennas in VHF / UHF / microwave DX activities. No network or fancy maps usage, so it can be used even in remote locations.

The ICOM IC-7610 SDR HF/50MHz Transceiver Basic Manual in English PDF File 13 MB

A Quick start guide to NPR New Packet Radio on 70 cm band by the NPR author Guillaume F4HDK. This presentation introducte basic concepts of this niew digital protocol, and guide the user to the first modem configuration both of client and master modems. Includes a final recap of commands.

The N1HFX thermal cooling fan controller project details a practical circuit designed to manage cooling fan operation based on temperature, a common requirement for high-power amateur radio equipment. This build utilizes a **LM34** temperature sensor, providing a linear voltage output directly proportional to Fahrenheit degrees, simplifying the control logic. The circuit's core functionality involves a comparator that activates the fan when a preset temperature threshold is exceeded, ensuring efficient cooling and reducing unnecessary fan noise. This controller is particularly useful for amplifiers, power supplies, or transceivers that generate significant heat during operation. The design incorporates a _TIP120 Darlington transistor_ to drive the fan, capable of handling up to 5 amps, making it suitable for a range of fan sizes and current requirements. Field results indicate stable temperature regulation, preventing thermal runaway in enclosed environments. Construction involves readily available components, making it an accessible project for hams looking to optimize their station's thermal management.

A PDF Presetation from the W0DXCC Forum on how to improve the performances of the popular Yaesu FT-2000 transceiver

Supporting wire antennas with squid poles

Utility-Driven Tradeoff Analysis, if you want to geto on the microwave bands , you will have to choose the proper antenna for your operating conditions. How to decide is not always easy, and you may also decide to build your own antenna.

A classic document originally presented in Proceedings of the Institute of Radio Engineers in 1937 and is, still today, the standard referenced by the FCC, text books and many amateur radio publications.

An interesting guide to aerials comparing height, gain and angles

A light and sturdy Quad for 10 and 15 meters. Basic Quad antenna design considerations. Building and assembling a dual band HF QUAD antenna, designing and joining cross-arms and boom, assembling spreader and element wire installation notes. QST article.

Midwest Mountain Thunder CB Radio Group is a group of CB SSB operators that started in the Midwest as a branch off of the Washington State group. good clean radio

The Kenwood MC60A with preamp, suffers from RF feedback, a search on the web reveals the extent of the problem. This document explain how to fix this problem.

Switching Regulator Basics By Mike Martell N1HFX

A very well done presentation about End-Fed Half-Wave antennas. This PDF document contains a summary of experiences in how to build custom EFHW antennas. Includes an interesting comparison table of UnUn configurations with recommended toroids, Wire size, turns and capacitors. An useful recap on common errors in building homebrew EFHW Ununs completes the document.

Building an amateur station for competitive radiosport involves a number of critical steps, regardless of the band or bands you focus on. These include, but are certainly not limited to: Station layout, Equipment interconnection and switching, Inter-station interference, Antenna selection. Radio interface with the logging program, CW and voice keyer integration, Rotator control

A two element beam antenna for ten meters band. This home-brew two-element beam is the perfect introduction to rolling your own gain antenna

Acom 1010 operating manual in english PDF File

This tutorial provides background information on the decibel and instructions for performing calculations involving decibels. This tutorial combines information from several authors, including Bob DeVarney, W1ICW; Walter Bahnzaf, WB1ANE; and Ward Silver, NOAX

This article will explain a few of the ways author use an external SDR and Linrad to enhance his K3 experience. Linrad is one of many available SDR receiver programs. The same could be done with any radio that lets you access its IF frequency output. Article from NCJ Nov Dec 2019

The Homebase-10 is a wire halo antenna for 10m built with DIY store parts, effective despite its small size. Includes a dual-band version for 10m and 6m with gain around 0 to -2dBd, near omnidirectional pattern, and horizontal polarization. Overview based on a 2008 Practical Wireless article.

Article appeared on 73 amateur radio today in 1999 on how to unlock the secrets of sending precise Morse Code. Article contains hints on how use the stright key and the sideswiper key, but even the electronic keyers or the semiautomatic keys.