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The project in this article illustrates how to do this in a simple and low cost way so that you can easily access the microwave bands using the existing HF or HF/VHF transceiver as IF.

CERT Communications Team Procedures Alinco DJ-191 quick reference in a four pages PDF file

This is a compact three transistor regenerative general coverage receiver with fixed feedback. The sensitivity and selectivity is relative good, especially on the LF and MW bands, as can be expected with this simple design.

Complete microphone wiring handbook for most popular radio transceivers provided by Astatic Microphones.

Complete plan for making a 2-meter J-Pole antenna. This drawing in PDF File includes a detailed list of the parts needed to assemble the Jpole antenna for 144 MHz.

Have you been looking for an easy way to measure power or SWR at 1296 MHz? One thing is certain, it is not easy - simply because the normal range of SWR meters that most of us have is not up to 1300 MHz.

A collection of 450 MHz Cheap Yagis that have proven great portable operations, back-packing and transmitter hunts, and are something inexpensive you can throw up in the attic for that weak repeater

Presentation of the QO-100 the first geostationary OSCAR from Qatar by AMSAT-DL

Mini-Operating Guide includes useful hints on Using the HM-133 Microphone, Basic Operation, Operating through a Repeater, Programming a Memory Channel and Assigning a Memory Channel to a Memory Bank

Although most Preselectors are designed with an internal T/R relay, theoretically enabling direct insertion between the transceiver and the antenna, there is a problem when running CW, especially when running full QSK. The switching time of the internal relay is too slow to follow full QSK. The best way to avoid this problem altogether is to insert the Preselector directly into the transceiver’s RX antenna line, thus avoiding entirely the need to switch the Preselector in and out.

This presentation applies to HF / VHF / UHF antennas and is about 14 different type of antennas suitable for indoor od apartament installations

Operating on Airplane scattering. Scattering of radio signals by airplanes. An introduction to operating ariplane scattering, using aircraft to redirect RF that would otherwise be lost in space. Antenna Pointing, Doppler Shift/Digital Modes, using digital modes to operate airscatter.

Have you ever thought of setting up a portable HF station for an activity like the Field Day ?

All available frequencies & offsets configurations for repeaters can be downloaded as database for Kenwood MCP-2A memory channel programming software for TM-D710 & TM-V71. Zip file is no more available from the author, but the full table of frequencies is still online

An explanation of the different procedures and definitions that are commonly used for blocking dynamic range (BDR) measurements. Dynamic range in general is the ratio between the weakest signal a system can handle and the strongest signal the same system can handle simultaneously without an operator switching attenuators or turning volume potentiometers

This morse key and buzzer design only requires parts that one may already have or are easy to find on the web. There is nothing critical except that the contacts must meet when the key is depressed.

The Icom IC-7300 is a popular SDR transceiver known for its excellent performance in ham bands. However, users have reported issues with reception reliability outside these bands due to ADC aliasing. This phenomenon occurs when the sampling rate of the radio interacts with frequencies outside the intended range, leading to unwanted signals being received. For instance, when tuned between 30 to 36 MHz, users may inadvertently pick up WFM broadcast signals or PMR communications due to aliasing effects. This guide outlines modifications to improve the IC-7300's performance by addressing the low-pass filter design, which is crucial for reducing interference from these unwanted signals. The proposed modifications involve adjusting the low-pass filter on the PA unit to better attenuate frequencies that cause aliasing. Measurements indicate that the original filter design allows significant signal leakage, leading to false receptions. By implementing the suggested changes, users can achieve a notable reduction in unwanted signals, enhancing the overall functionality of the IC-7300. While the modification requires careful soldering, the benefits in performance make it a worthwhile endeavor for serious operators looking to optimize their SDR experience.

A 3 band dipole antenna for 40-80-160 meter bands, It's made with easily available materials and is designed for inverted V mounting. The antenna is shortened for these bands, but still manages to make contacts in 80m and 160m with stations in Canada and the USA. The construction details are provided, including the dimensions of the antenna elements and the traps. The antenna is easy to build and provides good performance in all three bands. In Italian.

A document that will guide you on Coaxial-Cable trap optimization process to gain on global antenna performance and on increasing effective bandwidth.

Collection of several topics on antenna tuners and their performance. Why use an antenna tuner? How does an antenna tuner…tune Does an antenna tuner fool the radio? Will an antenna tuner waste power? Can an antenna tuner help get more power to the antenna?

Experimenting with capacitive antennas for 40 and 80 meters band. A very space-saving antenna with good receivings caracteristics

A QST Article published in November 1922 is about the origin of Beverage antennas, an unidirectional antenna type that was discovered and experimented for the first time in that period. This article is the introduction to beverage antenna theory, by the homonimous autho H. H. Beverage.

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

Unlock the secrets of RF signal optimization in a presentation covering Balun essentials, diverse types, SWR Analyzer checks, revealing results, Ferrite impedance measurements, and practical applications on feeders and house conductors.

Operaring portable during field day by VK4ADC

Recent researches seem to support the hypothesis that Sporadic E propagation could be connected to presence of thunderstorms.

This article describes a multi-band antenna design for amateur radio enthusiasts by G3FEW. The antenna is designed to cover at least five HF bands with low SWR and without the need for an ATU. It is also designed to be easy to construct and adaptable for different locations. The antenna is a full-wave dipole with traps at the quarter-wave points. The traps are used to tune the antenna to different bands. The antenna can be fed with a 4:1 balun. The article includes instructions for building the antenna, as well as information on the theory behind its operation. The author also discusses the results of his tests with the antenna. This multi-band antenna is a well-designed and versatile antenna that can be used by amateur radio enthusiasts on a variety of bands. It is relatively easy to construct and can be adapted for different locations.

Around 17% of the U.S. population experiences some degree of Dyslexia, a condition affecting language processing that can hinder amateur radio license candidates, often leading to repeated exam failures despite diligent study. This resource outlines methods for Volunteer Examiners (VEs) and Elmers to identify and assist candidates with cognitive disorders like Dyslexia and **ADHD**, which affects approximately 4% of U.S. adults. It emphasizes recognizing patterns in missed answers, such as spatial placement errors on answer sheets, and suggests reading questions aloud as an accommodation. The author, NC4FB, shares a structured approach developed over three years, involving extensive candidate interviews and a self-study program. This program utilizes specialized software with keyword highlighting and a unique font to improve comprehension for Dyslexic/ADHD candidates. It also incorporates **MP3 audio files** for subelement questions and correct answers, providing an alternative study method for those who benefit from auditory learning. Key elements of the support strategy include repetition, positive reinforcement, and timely progress updates, often visualized with a color-coded table tracking scores of 85 or higher. The goal is for candidates to pass three consecutive sample exams with at least 85% before attempting the actual license exam, demonstrating mastery of the material.

This PDF guide provides detailed instructions and diagrams for constructing a fan dipole antenna, a popular choice among hams for multiband operations. The guide covers the design, materials needed, and installation process, offering step-by-step guidance to help hams set up an effective antenna system for their radio operations.

This HOWTO explains in detail how you can use the Kenwood TS-590S USB, COM and ACC2 ports for digital operation, set up the radio for digital data and digital voice operation

A document that includes a list of all countries implementing CEPT licence, with detailed information on licence types like standard CEPT, CEPT Novice and HAREC. A full list of frequencies, and call signs schemas to be used by foreign operators, compiled by Hans Schwarz, DK5JI

Yaesu FT-710 AESS MF/HF and 6-Meter Transceiver review on QST

Modifying the Collins KWM-2 for Serious CW Operation, Make this old SSB workhorse perform like it should on CW.

Receiving **GOES-16** and **GOES-17** weather satellite imagery requires a specific hardware and software configuration, detailed in this practical guide. The author outlines the necessary components, including a Raspberry Pi, an RTL-SDR dongle, a suitable LNA with SAW filter for 1.69 GHz, and a parabolic grid antenna. This setup enables direct reception of high-resolution weather data, a fascinating aspect of amateur radio satellite operations. The installation process begins with preparing the Raspberry Pi, followed by updating the system and installing essential dependencies like `git`, `build-essential`, and `cmake`. A critical step involves compiling and installing `librtlsdr` from source, ensuring proper driver setup and blacklisting conflicting DVB drivers. The guide then walks through testing the RTL-SDR dongle to confirm device recognition and troubleshoot common issues like USB power or driver installation problems. Finally, the instructions cover cloning and building `goestools`, a software suite essential for processing the satellite signals. This compilation, while time-consuming on a Raspberry Pi, is crucial for decoding the raw data into usable imagery. The guide concludes with the initial steps for creating the `goesrecv.conf` configuration file, preparing the system for active satellite reception.

If your multiple transceiver station is suffering of intrastation interference, this handy and inexpensive band pass filters and help you. QST article Sept 1988

Learn how to build a simple 12vdc azimuth and elevation motor unit for the Arrow Satellite Antenna to improve your FM satellite communication experience. This DIY project involves using a camera tripod and basic materials like aluminum tube and standoffs. Get detailed instructions, including the gearhead motor product number for optimal performance. Discover where to purchase the necessary components and stay updated on alternative motor options. Enhance your ham radio operations with this homemade rotator setup, designed for easy satellite tracking and communication. Share feedback and connect with other radio enthusiasts for more tips and ideas.

Article on portable HF antenna where author diverge about antenna efficiency versus size based on his personal experience on using HF antennas during portable operations

This page details (in brief) the component changes to modify a Cybernet series 27MHz CB transceiver to 50MHz.

DXFile is a Windows shareware application designed for amateur radio operators, providing comprehensive log management capabilities. The software, developed in Pascal, facilitates real-time and deferred QSO entry, automatically populating fields like frequency, mode, and DXCC country based on user input and system time. It includes features for searching, modifying, and deleting QSO records, with options to sort logs by date, callsign, or entry order. The program offers various printing functions, including QSL card labels in multiple formats, and can generate standard logbook printouts. Beyond basic logging, DXFile integrates modules for tracking progress towards major operating awards such as DXCC, _IOTA_, WAZ, WAS, DDFM, and DIFM. It provides detailed summaries of contacts by band and mode, including graphical representations of HF traffic. A dedicated QSL Manager module assists in processing received QSLs, allowing users to mark confirmations and print multi-line QSL labels. The application also incorporates a DXCC list viewer, which can be updated to ensure accurate country and zone data for logging and award tracking. A distinctive feature is its HF propagation prediction module, which calculates optimal frequencies and signal levels for paths between **250 km** and **6000 km**, considering both E and F layer ionospheric conditions. This module helps operators determine the best times for long-distance contacts. Additionally, DXFile includes a _Web-Cluster_ interface, enabling connection to various DX cluster servers like DXLITE, DXSCAPE, and NC7J for real-time spot information.

Make your own dipole for 40 and 80 meters band, assembling standard product parts like 40 meter traps, the 1:1 balun and insulators

The document discusses the classifications of sunspots and their potential for solar flare activity, categorizing them into Alpha, Beta, and Delta groups based on their magnetic field characteristics. It explains how these classifications relate to the likelihood of solar flares, ranging from minor to extreme events. The report also outlines the geomagnetic indices and conditions that affect high-frequency (HF) radio propagation, emphasizing the effects of solar flares on radio communication and geomagnetic storms. The information is geared towards amateur radio operators, providing insights into how solar activity influences HF radio operations.

List of Worldwide HF Beacons published by RSGB. The beacon service is a vital part of amateur radio propagation knowledge. Updates to the HF list, which is is a heavily edit form of the G3USF list, are continued by the current committee. It now only contains beacons that are known to be active and have been heard recently.

Official PDF guide to WSJT-X FT8 SuperFox operating mode published on June 2024 by Joe Taylor, K1JT

This article is an attempt to shed some light on this misunderstood component, covering topics like why you need a common mode coke, what it does, what properties it should have, ho to build one and how to measure its performance.

Practice these operating techniques so you will be ready to capture that 100-point bonus on Field Day. QST Article

Raspberry Pi Telemetry Station project by Burns Fisher, WB1FJ , Chris Thompson G0KLA/AC2CZ. A step by step guide on Building a Fox-In-A-Box The Easy Way, A Prebuilt SD Card Image or from scratch.

This project introduces the SN 1/8 mobile antenna, a compact and mechanically stable alternative to traditional 1/41/4 or 5/85/8 wave antennas. Designed for VHF/UHF mobile communications, this 20 cm antenna offers superior performance in moving environments. Its spherical radiation pattern enhances reflections, providing a 2 dB gain. Ideal for vehicle use, it is discreet, easy to install, and resistant to vibrations, making it a practical choice for mobile users seeking reliable and efficient communication. In French.

A Trapped dipole inverted V antenna for lower HF Bands. Construction details are for temporary installation. Permanent installations will require additional ruggedising and waterproofing however the basic electronics concepts remain the same. This project includes SWR plots for the three bands and pictures details of the homemade traps.

Track aircraft by reprogramming an inexpensive digital TV USB stick to receive Automatic Dependent Surveillance-Broadcast signals.

A step by step guide to install the NS Roofing filter into the Yaesu FT-2000