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A quarter wave vertical end-fed antenna for the 40 meters band. As all vertical antennas, also this aerial requires a good earthing system. In this project the ground is composed by twelve 4, wires buried in the lawn by using a spade to create a slit to drop the wire into.

The ultimate Keyhole Markup Language (KML) plugin for Google earth. Keyhole Radio is a unique and powerful RF planning interface, accessed by loading a Keyhole Markup Language (KML) overlay in Google earth.

The Wireless Institute of Australia (WIA) provides an official directory and database of Australian amateur radio repeaters, detailing their locations, frequencies, and operational status. The resource includes downloadable files in PDF and CSV formats, along with a _Google Earth KMZ_ file for visualizing repeater sites across Australia, including Amateur, CB, and Marine repeaters. It also references external resources for various digital modes such as _IRLP_, _Echolink_, _D-STAR_, P25, Fusion, and DMR, providing links to their respective information sites. The WIA repeater data is cross-referenced with the _ACMA database_ to ensure accuracy, with updates typically occurring twice a year. The directory employs a color-coding system, where purple indicates repeaters carrying the WIA broadcast or callback channels, and a 'W' status denotes operational repeaters with the weekly WIA broadcast. The resource also outlines policies for removing unlicensed or non-operational repeaters from the PDF listing after specific timeframes, while retaining them in the CSV file for potential reinstatement.

GW4ALG's _136 kHz Pages_ document the evolution of vertical antennas for the 2200m band, starting with a prototype mounted on a house wall. This initial design, despite achieving the first **395 km** GM-GW QSO, suffered from significant insulation breakdown, high RF losses due to proximity to the house, and difficult tuning adjustments. The author details the challenges of maintaining resonance and matching with a variometer in the loft, noting that adding three earth spikes offered no measurable improvement over a simple water tap connection. The subsequent experimental 12m vertical, relocated away from the house, significantly reduced dielectric losses and proved far more effective. This antenna enabled GW4ALG to set a world DX record on 136 kHz with a **1916 km** QSO to OH1TN, and an intra-UK record of **703 km** to GM3YXM/P. The resource further explores the use of helium-filled balloons to extend the vertical radiator, achieving heights up to 27m, typically 20m, for enhanced low-band performance. Practical advice on balloon types, inflation, and critical insulation between the wire and balloon is provided, emphasizing safety and avoiding arcing.

Improper grounding or earthing system can cause several unwanted RF interferences (RFI) to television sets, broadcast receivers, hi-fi sets and telephone sets. In this Article the author explain how to setup a proper radio shack grounding using coaxial cable and ceramic disc capacitor

Web based VHF-UHF RF planning powered by SPLAT! and Google Maps. Access via website, Android App or dynamic Google Earth interface.

APRS web map with weather, telemetry, messaging and a bulletin board. Google Maps and Google Earth views update automatically in real time. 14 languages.

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).

The "Shortish Guide to Using an Oscilloscope" elucidates the fundamental operation of oscilloscopes, detailing the purpose and function of vertical, horizontal, and triggering controls. It explains how vertical gain in Volts/cm and horizontal scale in sec/cm enable measurement of signal amplitude and timing, respectively. The resource differentiates between analog and digital scopes, noting that digital scopes often feature "soft" controls and are inherently storage scopes capable of capturing non-repetitive events. The guide dedicates a significant section to the critical role of oscilloscope probes, emphasizing their design to transmit waveforms without distortion or added noise. It explains the concept of a 10x passive scope probe, which reduces circuit loading by a factor of ten and eliminates waveform distortion through probe compensation, typically adjusted using a 1kHz square wave reference output. The document also provides practical advice on probe care and compensation procedures. Further sections address grounding considerations, explaining how a scope measures voltage relative to its chassis ground, which is tied to the protective earth. It offers troubleshooting steps for a blank screen and outlines essential good practices, such as checking input gain and probe attenuation, while explicitly warning against misusing probes or connecting the ground clip to mains voltage.

Upload an ADIF fiel and plot all worked grids in an online map. Support filtering by band, year and can export the output directly into a google map, or a google earth KML file

A complete guide to start operating EME. In this document, that is the result of several years of experimenting, the author summarize the steps to begin on Earth-Moon-Earth communications

Approximately 524,475 Brazilian amateur radio operators are cataloged within this resource, offering a comprehensive database for the South American region. Each entry includes geographical coordinates, enabling users to visualize station locations directly within Google Earth. This functionality supports DXers in identifying potential contacts and understanding propagation paths relative to specific Brazilian QTHs. The platform serves as a digital callbook, primarily focused on the Brazilian amateur radio community. It facilitates the lookup of callsigns and associated location data, which is crucial for award tracking, contest planning, and general operational awareness. The integration with mapping services provides a visual dimension to traditional callsign databases, enhancing the utility for operators interested in geographical aspects of radio communication.

This freeware application for Linux and windows, allows you to convert an ADIF file to a KML file so you can map your QSOs easily and open it with google maps, or google earth or any application supporting the KML format

This project is a python program used to plot the location of QSOs (radio contacts) on Google Earth or other mapping applications. It reads an ADI file of the QSOs and creates a KML file

A free web app that converts ADIF files into KML format for viewing on Google Earth or other KML viewers. Users can view QSOs on a 3D globe, click on station markers for details, and navigate the globe. The page provides instructions, features, limitations, and requirements for using the tool.

Analyzes the operational dynamics of the _IARU R1 VHF contest_, the world's largest 2-meter contest, focusing on factors enabling top performers to maintain consistent results amidst declining overall activity. The resource investigates the physical constraints that limit higher point totals, examining how technical capabilities, increased interference, and evolving station setups contribute to contest outcomes. It provides insights into the strategic and technical aspects of achieving high scores, such as the **1,000,000+ point** totals observed from leading stations. Compares the performance of various stations over time, highlighting the sustained success of top contenders and speculating on future trends in VHF contesting. The analysis delves into specific operational strategies and equipment choices that differentiate high-scoring stations, offering a detailed look at the competitive landscape. It also considers the impact of propagation conditions and operator skill on final scores, providing a comprehensive overview of the contest's intricate mechanics and the pursuit of maximum QSO points.

Discover a comprehensive solution for mapping Australian ham radio entities using data from the ACMA Public Register. This tool, developed in Delphi 7, generates KML files for Google Earth, showcasing repeaters, beacons, and operators across different prefixes. While respecting privacy regulations, the files provide valuable insights into the amateur radio landscape.

This is a theoretical look at propagation on 630-Meters and 2200-Meters using ray tracing software. It expands on the brief discussion in the ARRL Handbooks. The Earth's magnetic field affects 630-Meter and 2200-Meter band propagation. Lower ionization reduces absorption, aiding low-frequency propagation. Differences exist between bands, limited daytime sky-wave propagation. Sunrise/sunset show promise, yet mechanisms are unclear. Ducting possible at night in specific conditions. Negative ions enhance propagation. Inefficient antennas and high man-made noise are anticipated. Groundwave propagation is significant on 2200-Meters.