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The resource details the construction of a homebrew 50-watt FET amplifier, based on Don W6JL's _QST Homebrew contest_-winning design from 2009. It functions as an afterburner for QRP transceivers, providing a **12dB** power lift. The amplifier utilizes IRFZ24N FETs and covers the 80, 40, 30, and 20-meter bands, with the 20m LPF extending to 17m. Key technical aspects include an FT37-43 transformer for the input network, a relay-switched 3dB pad for lower bands controlled by an _Arduino Nano_, and an RF-actuated T/R switch. The LPF board integrates four relay-switched filters rated for 50 watts, using capacitors with a minimum 250VDC rating. Performance measurements indicate a power gain ranging from **4.4dB** on 20m to 8.1dB on 80m, with a required drive power of approximately 5 watts. The article also discusses thermal management, current limiting considerations, and component sourcing.

The RasHAWK team has used a Raspberry Pi as the basis for a networked RF sensor capable of supporting spectrum monitoring, signal intercept and direction finding (DF) operations.

A project for a 50 MHz moxon rectangle antenna

In this PDF article Zack Lau describe how to homebrew a four element yagi beam antenna for 50 MHz band, including how to build mounting blocks and tubing clamps to hold elements.

Why all the mystery surrounding baluns ? To use or not to use baluns

The Packet Radio beginners guide to packet radio operating by Buck Rogers K4ABT

A bycicle ham radio station setup, with full band coverage

Demonstrates various practical amateur radio projects and technical discussions through video episodes. One episode details cutting and retuning a _1/4 wave shorted stub_ from 101.7 MHz to 107.5 MHz to safeguard a transmitter's driver stage, alongside insights into advanced _160-meter antenna systems_ like eight-circle arrays and beverage antennas. Another segment covers upgrading firmware on an _ATS-20+_ receiver using AverDudes for improved display and functionality, and a detailed guide on using D-Star DR mode on an _ICOM ID-52A_ for international repeater programming. Additional content includes a deep dive into _OpenHamClock_ as a potential replacement for the HamClock project, updates on _Raspberry Pi 5_ running Trixie OS, and a review of the Choyong LC90 Internet radio with AI integration. The series also features "Ham College" episodes, which meticulously prepare viewers for the Technician Exam by covering topics such as antenna and transmission line measurements, SWR interpretation, and the functions of basic electronic components like rectifiers, relays, and transistors. Practical advice on coaxial cable characteristics, dummy loads, and proper soldering techniques is also provided.

A trap on the coaxial cable, also known as choke, helps to eliminate the sneaking of the reflected RF- energy to the shack. The trap can be made from the coaxial cable that feeds the antenna

After you have build this antenna, you may not need anything else. This article shows how to build a VHF j-pole antenna and how to protect it by inserting it into a PVC tube, the correct way.

In this article the author describes some new designs of ferrite loaded chokes for suppressing unwanted common mode currents at HF applied to feed lines like choke baluns, but also in the shack, applied to various coaxial, mains and data cables

Technical supplement with schematics of the Yaesu FT-2800M Yaesu Transceiver

The Icom IC-7300 is a popular HF transceiver among amateur radio operators, known for its advanced features and ease of use. However, integrating it with software like Ham Radio Deluxe (HRD) can be challenging due to compatibility issues. This guide provides step-by-step instructions on how to configure the IC-7300 to work seamlessly with HRD 5.24, the last freeware version available. It covers the installation of necessary drivers, setting up virtual COM ports, and configuring audio settings for digital modes. To begin, users must download and install the Icom USB driver, which creates a virtual serial COM port for communication between the radio and the computer. The guide details how to check for this new port and adjust the CI-V address settings to ensure proper communication. It also explains how to set up the soundcard settings in HRD for digital modes, allowing operators to transmit and receive audio effectively. Following these instructions will enable IC-7300 owners to maximize their radio's capabilities with HRD.

Butternut article on radials usage on vertical and ground plane antennas

A presentation of a HF multi-band sloper antenna. This antenna project is for low band operations, and antenna presented in this article works on 40 80 and 160 meters band. Article is in Polish.

Schematic diagram of the VLA 200 power amplifier by RM Italy

VHF Power amplifier VLA 200 english manual

Many Hams suffer from a cruel obsessive-compulsive disorder. They're driven to achieve the lowest possible SWR even when it is not necessary by WB8IMY

Designing and constructing portable wire antennas for HF operations, this resource explores several configurations including the _foldback dipole_ for space-constrained setups and an inductively shortened dual-band dipole for 20m and 40m. It details the calculation of inductance for shortened elements, providing a Visual Basic 6.0 program screenshot that illustrates determining coil parameters like turns and length for a **25.5 uH** inductor. The document emphasizes practical considerations such as adjusting wire lengths for optimal SWR, noting that a dual-band dipole achieved SWR below 2:1 on both 20m and 40m, with careful adjustment bringing it under 1.5:1. Further, the resource describes a half-wave antenna matched with a coaxial stub, a method often referred to as the _Fuchskreis_ in German amateur radio circles, to transform the high feedpoint impedance to 50 Ohms. This monoband solution, for a 20m application, uses a stub length of **2.98m** (0.216 lambda multiplied by coax velocity factor) and a shorted stub of approximately 48cm. The coaxial stub design is highlighted for its resilience to ground proximity, allowing it to be rolled up or laid on the ground with minimal SWR impact, making it highly suitable for portable QRP operations.

Download the Yaesu VX-8R Cheat Sheet PDF File

My Top Five Backyard Multi-Band Wire HF Antennas. A selection of the top 5 HF wire antennas for the backyard and for multi-band operation

Photo construction manual of a portable antenna made with two heavy duty whips by buddipole. In this article has been implemented a 50 MHz portable dipole.

Tips on winding wire coils used as inductive loads, traps, band-pass filters, are implemented in a number of amateur radio projects especially antenna projects

Project for DXers and experimenters alike. An old article publishes by 73 Amateur Radio magazine in PDF format, where all the components required to build your own HF spectrum analyzer may be found in a well-stocked junk box.

Win EA6DDlog is a freeware logging application for Windows, developed by EA6DD Biel. It integrates features from existing software like Swislog, Urelib, Logger, and HamRadio Deluxe, presenting a Multi-Document Interface (MDI) similar to Logger. The program prioritizes simplicity, practicality, and operational speed, allowing functionality even on less powerful PCs. It does not require a formal installation; users can run it directly from a portable drive or any directory. This logging utility supports CAT control through Omnirig by Alex Shovkoplyas, VE3NEA, which is automatically installed if not already present on the system. It also offers QSL printing capabilities and connections to online callbook services such as QRZ and HamQTH for contact information. EA6DDlog includes an automatic update mechanism that checks for new versions upon startup, requiring internet access. For Windows Vista users, disabling User Account Control (UAC) is recommended for proper update functionality. The software is part of a broader development effort aiming for cross-platform compatibility, with future versions planned for Windows Mobile, Linux, and macOS.

Building a Windom HF Antenna. A PDF file presentation about homebrewing a windom antenna for the HF bands with formulas for 40 and 80 meters bands and step by step guide on making a 4:1 balun to feed the antenna.

Find out how much to adjust the length of a quarter wave whip or a half wave dipole rather than the outright cut-and-try method.

Printable Quick Reference Card for Yaesu VX-7R

A home made 4:1 Ferrite QRO Bal-un with a FB 241-61 Type K

The resource details the construction of a multiband trap-style Inverted-V antenna designed for operation on 3.5 MHz, 7 MHz, 14 MHz, 21 MHz, and 28 MHz. It presents specific winding data for the traps, including the number of turns, wire gauge, and coil former dimensions, crucial for achieving resonance on the target bands. The document provides a parts list and a diagram illustrating the antenna's physical layout and trap placement. It outlines the process for building the traps using PVC pipe formers and specifies the required capacitor values for each trap. The design emphasizes a practical approach to achieving multiband operation with a single feedline, a common goal for HF operators with limited space. The document includes a table with antenna segment lengths for each band, allowing for precise replication of the design. It also offers insights into tuning and adjustment, ensuring the antenna performs optimally across the designated amateur radio bands.

Alternate means of raising your tower with readily available boat and engine hoists. Examples of working tower hoists with links to manufacturers.

Skin effect and proximity effect on making coils with stranded wire. An interesting comparison on making coils.

Construct a compact, 20 meter rotatable dipole antenna of durable weather worthy components supported at a single point obviating the need for multiple supports and multiple support ropes crossing the yard.

An interesting article on guanella baluns that cover several aspects of homebrewing 1:1 and 4:1 current baluns by KN9B

May 2015 Radcom Article on common-mode chokes that can be used for control cables, phone lines, but mostly on typical HF antenna systems. This article explain what common mode chokes does, why you meay need one, properties common mode chokes should have, how to build and measure performances.

**LDG Z100** automatic tuner repair focuses on toroid replacement and troubleshooting. The guide provides detailed steps for diagnosing and fixing common issues with the toroid, which is crucial for the tuner's performance. It includes specific instructions on disassembling the unit, identifying faulty components, and sourcing replacements. The document is technical, requiring familiarity with electronic components and soldering techniques. It emphasizes the importance of using the correct toroid specifications to ensure optimal functionality. Successful repair of the **LDG Z100** ATU restores its ability to match a wide range of antennas, enhancing transmission efficiency. The guide compares the performance before and after the repair, highlighting improvements in SWR readings and overall reliability. Practical application of this repair extends the life of the tuner, making it a cost-effective solution for amateur radio operators. The document serves as a reference for similar repairs on other models, providing insights into common issues and solutions. It is a valuable resource for those looking to maintain their equipment without resorting to professional services.

As used on the new GB3VHF 144.43MHz Beacon

Diamond W8010 Multiband Dipole Modifications

The **KC0KJF** personal amateur radio page provides a collection of resources for fellow hams, particularly those interested in operations within southwest Missouri. It offers detailed listings for **Missouri repeaters** on both 2 meters and 70 centimeters, serving as a practical reference for local VHF/UHF communication. The site also includes information about the operator's station setup and antenna projects, such as a dipole and a bazooka antenna, which can offer insights into basic antenna construction and deployment. Beyond local repeater data, the page features links to the FCC Part 97 rules, essential for understanding amateur radio regulations. The operator, licensed as a Technician Class since April 16, 2001, shares his journey from Citizen's Band Radio to amateur radio, driven by a lifelong fascination with shortwave listening. This narrative provides context for the resource's focus on practical operating information and foundational regulatory knowledge. Additional content covers specific equipment like the 2-meter/70-centimeter Arrow Antenna, useful for hams considering portable or fixed station VHF/UHF setups.

QST Magazine, 1991 July, review of the Kenwood TS-850S 160-10 Meter Transceiver

The Ameritron ALS-600 600-Watt HF Power Amplifier review by AD5X

This article is about a simple vertical end-fed-half-wave wire antenna for 10 meters that can be used in case of restricted space.

50MHz Collapsible 2 Element Mini Beam antenna, an overview the development of the 6MBA.

Ameritron QSK 5 PC mod for AL80B

A handy piece of test equipment useful for HF bands, can absorb a 200W modulated carrier for almost 2 minutes. It is housed in a tin and part filled with dry sand that helps in power dissipation

IARU Region 3 bandplan Revised 12 March 2019

An ham radio contest log sheet in a PDF US letter printable format, can be used for portable operations, free to print and download.

VK Contest Log (VKCL) is a free contest log software specialising in Australasian contests but also covering some international ones too. Author is SK, you can donwnload the latest version 4.15.

Globe-S for RTL1090 is a light radar viewer for RTL1090. It communciates via a HTTP interface and can be interfaced over long distances.

In this article the author provides some guidelines on how to solve a common problem when stacking different types of yagi antennas on the same mast, limiting the effects on gain and radiation pattern of both antennas