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The basics of using an oscilloscope, this article is meant for thiose with very little or no experience at all with electronics or oscilloscope.

Experimental Methods in DSP design. The author explains how a software defined radio works to help other amateurs with their learning. This set of tutorials takes you from how to write a single component to a fully working SDR.

How to setup the Yaesu FT-847 along to the PSTRotator under Windows 10 PC with Omnirig.

If you want to build your own common mode choke, this article explains how to measure the efficiecy of your choke before using it. In the examples has been used Amidon FT240-31 toroids.

How to install a BNC connector on a coaxial cable like the ELSPEC1030AF / HPF195RG and 58C/U cables

How many times have you heard the advice to coil a few turns of coax at the antenna end to form a choke. How to find out if your common mode current choke really works

How to send and receive QSL cards at RSGB

Surprisingly, although PCB soldering is the core process of electronics assembly, few people do know how to solder reliably

A hexagonal beam is a form of the Yagi antenna which is based on parasitic principles developed early in the last century in Japan for achieving gain in one direction.How HexBeam antennas works. A hexagonal beam operates exactly like Yagi antenna, but instead of a driven element that is straight like a dipole, it is a wire bent into the shape of the letter M.

Illustrates the fundamental principles of radio repeaters, detailing their role in extending communication range beyond line-of-sight limitations. It begins by defining _simplex communication_ as a direct radio-to-radio link, effective only when no obstructions impede the signal path. The resource then introduces the concept of a repeater (or base station) strategically positioned on elevated terrain, such as a mountain, to overcome geographical barriers. The article clarifies the repeater's operational mechanism: it receives a signal on one frequency and simultaneously re-transmits it on a different frequency, enabling users on opposite sides of an obstruction to communicate. This _duplex operation_ is likened to satellite communication for VHF propagation, but with a fixed terrestrial station. Specific examples of signal paths are provided, showing how a handheld radio transmits up to the repeater, which then relays the message down to another user, effectively bypassing obstacles like hills or large buildings.

I have RFI, now what– Locating it. This article is the first of a three parts article, that covers the problem of locating the RFI source. Author make use of an SDR receiver to locate RFI emissions. Ai interesting RFI location process diagrams helps on following the various phases, permitting the discovery of almost 75% of the RFI issues.

The basics of through-hole soldering, the tools needed, go over techniques for proper soldering.

Learn how to register for a DMR ID on DMR-MARC and Brandmeister

A great way to provide a public service and maintain your skill as an operator is to be a net control station. Being net control is rewarding and not overly difficult.

A step by step instruction on how to upgrade firmware on the Tytera MD-380 DMR

This article provides a step-by-step guide for assembling a Raspberry Pi-based Satellite Tracker Interface, designed to work with Green Heron Engineering's RT-21 controllers and MacDoppler software. The guide covers hardware assembly, SD card image installation, and system configuration for satellite tracking.

Learn morse code with this online version of the popular morse machine. This version is currently working on Chrome browser only. This program teaches you to receive Morse code. It starts with a few letters and adds more when it sees that you are ready.

How to use AI (Artificial Intelligence) to identify Radio signals using a RTL SDR dongle and Linux (Ubuntu). This solution implement a framework using Keras and TensorFlow to learn and recognize the RF signals.

How to Design and Build a Field Expedient End-Fed Half-Wave Antenna for 20m, 40m and 80m. This Shorty 80m EFHW comprises a 49:1 autotransformer (to match the very high impedance at the end of a half-wave wire), a half-wavelength wire for 40m (also a quarter-wavelength for 80m), a loading coil and a short tail wire. The coil and the short tail wire (about 6 feet) make up the other quarter wave on 80m.

A home made battery charger 110-220 v AC providing from 1.25-24 v DC Adjustable at 8 Amps output power, with Short Circuit Protection Over Load and over charge Protection.

How to easily receive and decode CubeSat telemetry

Showing aircraft scatter reception in action.

This webpage explains how analog wide area two way radio systems were setup by various states before systems like VIPER, PALMETTO 800, or FLEETNET were established.

Build a low-cost 20m shower rod dipole antenna

Since 2012, the RTL-SDR is the simple and cheap way to give Software-Defined Radio a try. For about 25 euro you get a receiver covering much of the VHF and UHF range, and by either adding an upconverter, or using the direct sampling option, also the HF bands. They are so cheap because they are mass-produced as DVB-T receivers.

Due to the nature of PSK it is imperative that you maintain a very clean signal. In this page you will find examples of a clean PSK signal and one with excessive splatter, and a short guide on how to properly adjust your transmitter to assure a clean trace

Tutorial, How to call CQ as an HF QRP station in SSB/Phone. Calling CQ Basics, Calling CQ QRP or Portable

The article describes how to build a 12V emergency power supply for amateur radio stations. Starting with a basic jump-start system, the author upgraded it using a Group 27 deep-cycle battery and a 45W photovoltaic solar system, adding connectors and outputs for various devices. The system is portable, affordable (under $100), and capable of powering a station for 20 hours. The author emphasizes keeping batteries charged with a float charger and offers assistance to fellow club members interested in building their own power supply.

This page provides instructions and links to download the latest APK version of APRSdroid and the Mobile HUD for ham radio operators. It also includes information on manually granting storage permissions for offline mapping files on Android 11+ devices. The page offers guidance on setting up and using offline maps in APRSdroid with OpenStreetMap.org. Various mapping options and providers are mentioned, along with a recommendation to support the author on Patreon. Overall, this resource aims to assist hams in effectively utilizing APRSdroid for their amateur radio activities.

DX University publishes an operating guide for DXPeditions with 13 hints and tips on managing pileup

Thunderstorm effects on sporadic E propagation, Very long distance propagation in the 144 MHz band, Analysing the number of skips in multiple hop propagation

Controlling a rotator via computer can be costly, but a budget-friendly solution exists using an Arduino Nano and free software by Anthony K3NG. This setup allows for easy and enhanced rotator control, including screen and network management. Though initial software setup can be complex, pre-configured versions are available. Building and customizing the hardware interface is required, with comprehensive support provided by K3NG's resources.

The author shares a unique experiment with a 200ft Grasswire antenna—laying wire directly on the ground. Despite inherent losses, the setup enables successful radio communication with a Kentucky station, highlighting the antenna's practicality for portable use with minimal power.

A vertical antenna project for POTA operations. This shortened antenna is aimed to work from 20 to 40 meter band implementing a loading coil, with an additional wire lenght, determined by on field testing and tuning.

A DIY cantenna can extend your WiFi range by building a 2.4 GHz high-gain antenna using accessible materials. The design, based on waveguide principles, uses a cylindrical tube to capture WiFi signals and can even connect to access points half a mile away in ideal conditions. While the ideal tube diameter was hard to find, a 4-inch aluminum dryer vent was chosen despite theoretical limitations. The cantenna offers a cost-effective, functional boost for your wireless network.

This comprehensive three-part guide examines baluns (balanced-to-unbalanced devices) and their critical role in ham radio antenna systems. The author explains how baluns prevent common-mode currents on feedlines, which can distort radiation patterns and cause unwanted RF in the shack. Various balun types are analyzed, including coiled coax chokes, ferrite-core designs (W2DU), and toroidal-wound versions (Guanella/Ruthroff). Construction techniques for 1:1, 4:1, 6:1, and 9:1 current baluns are provided with practical guidance on wire selection, winding methods, and ferrite core properties. The article emphasizes that proper balun implementation is essential for optimal antenna performance, especially with directional arrays.

This article addresses the issue of unwanted RF in amateur radio setups and introduces a practical method to measure common-mode currents (CMC) using a homebuilt RF meter. The meter, constructed with readily available materials, measures unwanted RF on the coaxial cable shield by inductively coupling to the shield using a split-bead ferrite. The article provides detailed instructions on building the meter, interpreting measurements, and using ferrite chokes to mitigate RF interference. Emphasis is placed on the importance of verifying CMC levels and installing chokes to improve equipment performance.

Building a radio repeater enhances communication by extending signal range and overcoming obstacles like mountains or buildings. This guide explains the fundamentals of radio repeaters, their function, and a step-by-step DIY approach. Key steps include conducting a site survey, selecting an optimal installation location, and configuring the system with suitable equipment such as the Retevis RT97 series. Proper placement, antenna setup, and testing ensure effective operation, making this process accessible for enthusiasts aiming to improve communication reliability and range

Discover how to easily listen to amateur radio bands with insights from Frank SWL, an experienced radio enthusiast. This guide covers essential tips for tuning into frequencies between 10 meters and 160 meters using modern tools like Web SDR and Kiwi SDR. Learn about identifying callsigns, understanding Q codes, and optimizing your antenna setup for better reception. Whether you're a beginner or an experienced listener, this article provides practical advice for enhancing your radio listening experience in 2025.

Author proves a swift and enjoyable method for scanning and exhibiting cherished QSL cards in the shack. Scanning each QSL card and displaying them. A Modern Solution for Scanning and Showcasing Your Favorite QSL Cards

A blog post about experimenting AI on writing blog post and creating pictures. This page includes also a youtube video by VE4VR experimenting ChatGPT over ham radio bands.

This article discusses the evolution of portable amateur radio operations, focusing on optimizing backpack-carried equipment for outdoor use. The author shares his journey from using wheeled carts to developing an innovative backpack-mounted antenna system, emphasizing the transition from high-power (QRO) to low-power (QRP) operations to reduce weight. The piece details practical solutions for antenna mounting, equipment selection, and portable operations in challenging terrain, particularly along Ontario's Niagara Escarpment. The author's approach prioritizes mobility and functionality while maintaining effective radio communications in remote locations.

Galvanic corrosion, a destructive process triggered by dissimilar metal contact in a corrosive electrolyte, poses a significant threat in antenna manufacturing. With aluminum and stainless steel components commonly involved, unaddressed corrosion can lead to white particle accumulation, causing long-term damage. Awareness of the galvanic series and the application of protective coatings like Alumslip can mitigate this pervasive issue, ensuring a prolonged antenna lifespan.

This documentation effort is intended to outline some of the primary steps to take in activating a SOTA Peak. It includes some of the planning steps, the activation, and post-activation steps. This outline is designed to serve as a general guideline for SOTA Activators

A guide to programming a Yaesu FT5DR under Ubuntu Linux using CHIRP and the USB-68 Cable. This operation that is usually very simple and easy to do under Windows, need more configuration efforts under linux os.

This article explains how LoRa parameters impact data rate and range when setting up a LoRa transceiver. It covers the basic concepts needed to understand different LoRa parameters and their effects on modulation. By adjusting parameters, you can achieve fast data transfers or extend transmission range. The post also offers a calculator to determine on-air bitrate based on input parameters. Understanding LoRa parameters is crucial for optimizing performance and achieving desired communication outcomes.

This document provides a comprehensive guide on renewing an US amateur radio license through the Federal Communications Commission (FCC) using the new COmmission REgistration System (CORES). Published on QST October 23, it outlines the necessary steps for creating a CORES account, associating it with a Federal Registration Number (FRN), and completing the renewal application. Key points include the requirement of a $35 fee for the renewal process, which must be paid online after the application is submitted. The guide emphasizes the importance of logging into the FCC License Manager system during the renewal window and provides instructions on how to navigate the renewal process, including obtaining confirmation and access to the renewed license. Additionally, it offers contact information for FCC support and links to further resources for assistance.

Learn how to modify your Baofeng 888s radio to use in an Allstar node. This article provides step-by-step instructions on programming the radio with suitable frequencies for amateur radio use, including tips on using the Chirp program. Make sure to use a cable with a Genuine FTDI Chipset for easy connection to your computer. Avoid transmitting on pre-programmed channels to prevent trouble. Follow the guidelines provided to customize your radio settings and ensure a smooth modification process. Visit the link for Chirp program download and consult Miklor for programming assistance.

Learn how to connect your AllStar Node to 44Net in this blog post. Discover step-by-step instructions and tips to make the process easier for hams interested in expanding their networks. Find out how to improve your communication capabilities and enhance your overall ham radio experience with this helpful guide.