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This project focuses on testing and comparing various antennas for receiving ADS-B (Automatic Dependent Surveillance-Broadcast) signals, utilizing software tools like RTL1090 and Virtual Radar with an RTL-SDR dongle. The goal is to evaluate the reception range ("ReceiverRange") and performance of different antenna types when tracking aircraft signals, particularly around the Amersfoort area. The project includes a comprehensive photo album documenting the antenna designs and setup processes, serving as a valuable resource for enthusiasts building ADS-B reception systems

The exchange of QSL cards by radio amateurs is a practice that is almost as old as radio itself. History of IARU QSL Bureau, evolution of the system

Constructing an effective antenna support system often involves safely elevating wire antennas into trees or over obstacles. This resource details the build process for the WT8WV "Colossus" air cannon antenna launcher, a pneumatic device designed to project a pilot line over elevated structures. It specifies the use of readily available PVC pipe components and standard hardware, outlining the exact materials required and providing step-by-step assembly instructions for a robust, low-cost solution. The article presents a practical alternative to traditional methods like slingshots, emphasizing the launcher's utility for Field Day operations and general antenna deployment. It includes a comprehensive list of parts, such as 2-inch and 1-inch PVC pipe, various fittings, a sprinkler valve, and a bicycle pump valve, detailing their integration into the final assembly. The total cost for materials is estimated at around $40 per unit, making it an accessible project for many radio amateurs. Crucially, the guide incorporates essential safety precautions for operating a pneumatic launcher, covering aspects like pressure management and projectile selection. It also features multiple photographs illustrating the construction phases and the completed device, offering visual clarity to aid builders in replicating the design.

Learn how to design and analyze a folded trifilar antenna for the 80-meter band. Based on a description from RAF antennas between 1940 and 1970, this article provides step-by-step guidance on modeling the antenna, calculating resonance frequency, adjusting dimensions, and verifying performance. Perfect for hams looking to improve their antenna setup for better transmission and reception on the 80M band.

This article presents an RF Choke featuring an 11-bifilar turn winding of #14 house wire on a Fair-rite FT240-31 toroid. The choke is enclosed in a 3D-printed case from Thingiverse, though this may pose thermal concerns at higher power levels. With SWR concerns up to 30MHz, the author plans to employ two series chokes at the rig input for improved performance. This choke offers versatility for portable use, with potential mismatch resolution using an antenna tuner. Further testing is anticipated upon the arrival of new cables.

Replacing two ceramin filters of a Yaesu FT-857 by desoldering and soldering new ones.

The FT-991 is a nice small size and lightweight radio, it is perfect for portable operations. It can be carried along with a laptop computer as hand luggage in airplane. The weak point of this radio, is it does not have a separate RX antenna capability. Therefore i decided to add this feature. On the back side of the radio a BNC connector is added to connect the RX antenna and a switch is fitted to select between RX antenna or main antenna.

Optimizing a QRZ.com page involves adding essential callsign data, ensuring correct _Maidenhead Gridsquare_ and DXCC information in the Detail tab, and populating the Biography section with relevant station details. Operators should include their operating conditions, specific country references like WAB square, club affiliations, and detailed QSL information, specifying preferences for electronic confirmations (e.g., _LoTW_, Clublog) and paper QSLs (direct, bureau, SASE). The guide emphasizes the importance of accurate data for electronic logging software integration, which fetches Gridsquare, DXCC, and CQ/ITU zones to populate contact logs correctly. Further enhancements include leveraging the QRZ.com photo gallery for images and setting a primary image that logging software like _Log4OM_ can display. Advanced customization involves embedding external services via HTML source code. Examples include integrating HamAlert for DX Cluster spots, Clublog for log searches and Online QSL Requesting (OQRS), and Parks on the Air (POTA) statistics widgets from WD4DAN. Additionally, live weather information from Weather&Radar and solar data banners from HamQSL can be embedded, providing real-time environmental context for visitors to the QRZ page. These embedded tools require creating accounts on respective platforms and often involve copying specific source code snippets into the QRZ biography's HTML editor, ensuring callsign placeholders are updated.

SkyRoof is an open-source, 64-bit Windows application designed for amateur radio operators and satellite enthusiasts, combining satellite tracking and Software Defined Radio (SDR) functionality in a unified platform. The software provides real-time satellite tracking, pass predictions, and visual representations through Sky View, Earth View, and Timeline displays. It features an SDR-based waterfall display covering VHF/UHF satellite segments with Doppler-corrected frequency scales, automatic satellite labeling, and visual tuning capabilities. SkyRoof supports various SDR devices (Airspy Mini, SDRplay, RTL-SDR), external transceiver CAT control, and antenna rotator integration. The application automatically downloads satellite data from SatNOGS and other sources, offers voice announcements for satellite passes, and includes comprehensive frequency control with Doppler tracking, manual corrections, and RIT functionality for enhanced satellite communication operations.

A real-time, responsive map view of APRS (Automatic Packet Reporting System) information, CWOP (Citizens Weather Observer Program), and other APRS-IS sources across the world. The N2RWE Real-time APRS Map leverages cutting-edge technologies and custom software to present a dynamic and user-friendly platform for visualizing Automatic Packet Reporting System (APRS) data. This web application aggregates real-time station locations from various public sources, offering a comprehensive view of APRS activity. It caters to both novice and experienced users by providing features like Maidenhead Grid maps, station lists, license plate searches, and advanced tools for geolocation, address lookup, and data analysis. Additionally, the platform integrates with Summits on the Air (SOTA) information, enhancing the experience for SOTA enthusiasts. By actively supporting the #APRSThursday net, the N2RWE Real-time APRS Map fosters a collaborative environment for the APRS community.

This page show a list of repeaters in north america transmitting from 28 MHz to 29 MHz. The most of them are in the 29.620 to 29.700 frequency range. Some repeaters may be active and on the air while others may not

This Arduino project explores long-range RF communication using EBYTE E32 1W LoRa modules (either E32-915T30D or E32-900T30D) paired with ESP32 microcontrollers featuring OLED displays. The setup leverages the modules' Semtech SX1276 chip with amplifier to achieve up to 1W transmission power—significantly more than the chip alone provides. Unlike other LoRa implementations, these modules include a microcontroller that simplifies interface through UART rather than SPI. The documented implementation includes proper wiring between components and Arduino code that configures the module, displays received messages on the OLED screen, and transmits messages every two seconds while keeping power consumption manageable.

How to repair and calibrate a used Bird model 43 wattmeter.

This article explores the marriage of amateur radio and bushcraft, advocating the pleasure of setting up a portable station in nature rather than operating from the confines of a vehicle. The Parks on the Air (POTA) programme is highlighted as a catalyst for outdoor radio activities. The author shares his experiences and techniques, from transporting equipment into the wilderness to setting up shelters and antennas. Knot tying skills and the use of frogs are emphasized for efficiency, and a unique method for launching wire antennas is described. The article emphasizes the synergy between amateur radio and bushcraft skills, enhancing the enjoyment of radio operations in wilderness environments.

The QRP Cluster provides a dedicated platform for _QRP_ (low power) amateur radio operators to self-spot their on-air activity. This web-based service allows users to post real-time information about their current operating frequency, modulation mode, equipment used, and transmit power. It facilitates QRP-to-QRP contacts and helps other low-power stations locate active QRP signals across various bands. Unlike general DX clusters, the QRP Cluster focuses exclusively on low-power operations, fostering a community for QRP enthusiasts. It enables operators to share details such as **5 watts** or less output, often specifying antenna types or unique portable setups. The platform supports the discovery of QRP stations for casual QSOs, contests, and award hunting, enhancing visibility for stations that might otherwise be overlooked on higher-power clusters.

A two tone generator is an essential test gear made with just four transistors that helps you evaluate your amplifiers, mixers, receivers for distortion. Distortion makes all the difference between a pleasant receiver and a horrible sounding one, between a clean transmitter and bad, splattering one on air.

The field strength meter (FSM) is a very useful addition to any HAM toolbox. If you are messing around with antennas, or building PA's, or trying to repair some TX gear, the FSM will come to your rescue when there is doubt about the output level.

Discover how the author, KK4Z, has perfected his Frankentenna over the years for portable operations, especially for Parks on the Air (POTA). Learn about the components sourced from different companies like Buddipole and Chameleon, allowing for versatility as a vertical antenna, endfed with a counterpoise, or even a dipole. The article also covers specific tweaks and modifications made to enhance performance. Ideal for hams looking to optimize their portable station setup with a reliable and lightweight antenna solution.

The PA0FRI Unbalanced/Balanced ATU is a home-built antenna tuner designed to efficiently match a W8JK 2-element beam antenna fed with a 450-ohm twin lead. Based on PA0FRI’s S-Match design, it optimizes energy transfer while maintaining balance, reducing losses, and ensuring proper radiation. The tuner uses a roller inductor, air variable capacitors, and a T200 iron powder coil, allowing fine-tuning across 14-50 MHz. Extensive lab tests confirm minimal attenuation and precise impedance matching, making it a reliable and efficient ATU for balanced antennas.

This project builds into a box into which you plug a Morse Code Key. Using the Morse Key creates realistic sounds so you can judge how well you Send. A great tool for beginners to improve Morse sending skills before going on-air

Boondock Echo offers a revolutionary communication experience with an internet-backed recording and playback device for two-way radios. It ensures clear, reliable communication in remote or challenging conditions. Key features include real-time recording, internet connectivity, seamless integration, playback flexibility, rugged design, and a user-friendly interface. Services include product training, hardware maintenance and repair, customization, and regular firmware updates for optimal performance.

Recently, at the Ballarat Hamfest, the author acquired an old Marine transceiver for just $10, charmed by its sturdy construction and waterproofing. Made by Findlay Communications in Sydney, this crystal-controlled transceiver had been dormant but was reinvigorated with minor fixes. A manual was sourced, and further repairs were made, including an ingenious crystal oscillator replacement using an Si5351a controlled by an Arduino. The refurbished radio, complete with a fresh coat of paint and added customizations, is now operational for 160m AM and 30m SSB. A successful and cost-effective restoration.

This PDF file provides detailed information on HF propagation for ham radio operators. It covers the principles of how radio signals travel over long distances, including factors that affect signal strength and propagation. The content is useful for hams looking to improve their understanding of radio communication and optimize their transmissions. Whether you're a beginner or an experienced operator, this resource offers valuable insights into HF propagation that can enhance your communication skills and efficiency on the airwaves.

The Pikes Peak Radio Amateur Association (PPRAA) serves as an ARRL Special Service Club, providing a calendar of events and activities for its members and the wider amateur radio community. The resource details upcoming events such as the USS Pueblo Memorial Museum Ships Weekend activations, a Cubical Quad Antenna Workshop, LARCFest, and various hamfests including Dayton Hamvention and Duke City Hamfest. It also lists on-air activities like a FreeDV digital voice mode event on 10 meters, a Black Friday Simplex Event on 2M and 70cm, and a 10m event for Technician class operators, emphasizing SSB privileges from 28.300 to 28.500 MHz. The PPRAA's event schedule includes educational opportunities like a Technician Class and a Soldering Workshop, alongside social gatherings such as the PPRAA Picnic and Car Show. Past event summaries highlight successful activities like the 2024 Megafest Raffle, Winter Field Day, and multiple fox hunts utilizing frequencies like 147.420, 147.480, and 147.540 MHz. The club actively supports POTA activations, exemplified by their AF0S park activation at Cheyenne Mountain State Park, and participates in historical commemorations like the USS Pueblo Memorial operations, demonstrating a broad engagement across various amateur radio facets.

The Belgian Air Force Amateur Radio Association sponsor of BAFARA Award

A simple, portable logger tailored for activities like Parks on the Air, Field Day, and more. HAMRS is a fast, user-friendly logging program designed for portable ham radio activities such as POTA, SOTA, and ARRL Field Day. Developed by Jarrett Green, it features an intuitive interface optimized for small screens and multiple platforms, including macOS, Windows, Ubuntu, Raspbian, iOS, and Android. HAMRS provides dedicated logging fields for portable operations, ensuring efficiency in the field. The desktop versions are free, while mobile apps require a small purchase. Its simplicity, cross-platform compatibility, and ease of use make it a valuable tool for amateur radio operators in portable settings.

The Wanted Alive (TWA) by OH2BUA is an online DX cluster service specifically tailored for digital mode enthusiasts, presenting real-time DX spots with a unique ranking system. Unlike traditional clusters, TWA sorts spots by decreasing DXCC most-wanted ranking, allowing operators to prioritize rare entities. It integrates data from various sources, including PSK Reporter and RBN, to provide a comprehensive view of current propagation conditions for modes like FT8, FT4, and JS8. This approach helps DXers quickly identify and pursue high-value contacts, optimizing their time on the air. OH2BUA's TWA provides a practical application for serious DXers by filtering the noise and highlighting the most sought-after DXCC entities. The service's focus on digital modes reflects the growing popularity of these efficient, low-power communication methods, offering a specialized tool that complements general-purpose DX clusters. By presenting propagation information through the lens of DXCC rarity, TWA assists operators in achieving DXCC awards and improving their overall DXing efficiency, particularly during contests or limited operating windows.

OM0ET manufacture high capacity variable air capacitor and tuning unit designed for Magloop antennas. OM0ET explains features and benefits of this antenna, such as easy assembly, wide frequency range, and improved efficiency. Ideal antenna setup for indoor or outdoor use, offering better QSO performance and radio listening experience. The author, identified as OM0ET, shares insights on the design and functionality of the equipment, making it a valuable antenna for portable operations.

Online impedance calculators grouped by types like Wire inductances, Toroid incuctances, Plane, PAD, Strap inductances, but even Core and Coax Inductances. Air core inductances and mutual inductance groups are also availbale. All these calculators let you input specific paramenters based on the inductor selected and will calculate specific incutance and related dimensions.

This article details the construction process for a simple, low-profile, multiband antenna designed for POTA (Parks On The Air) operations. It focuses on transforming a photographer's lighting tripod into a ham radio antenna, specifically addressing the electrical isolation of the top two radiating tube sections from the bottom support tube. The author, John VA3KOT, provides guidance on sourcing components such as the tripod (e.g., Amazon Basics Aluminum Light Photography Tripod Stand) and the telescopic whip (e.g., Buddipole's Long Telescopic Whip, measuring 9 feet 4 inches fully extended). The article also recommends using adhesive copper tape for contact areas and conductive grease to maintain high conductivity and prevent oxidation where tripod tubes connect. The total radiating element length is noted as 13 feet, formed by the whip and 4 feet of the tripod tubes. The construction does not require special tools but emphasizes careful assembly.

Getting started with Aircraft scatter, defined as the process of scatter radio waves of the body of a traveling aircraft in order to enhance the distance possible to bridge on VHF, UHF and microwaves. The ACS path, Equipment requirement and Operating techniques

This article explains the trick of how to shorten and lengthen pairs of radials to make a 2-band ground plane antenna. Included is a "Table of Multi-Band Possibilities" covering the range of 6 to 40 meters.

Repair of a Yaesu FT-1000 MP Mark V probably struck by lightning.

An FT-817 ceased transmission on the VHF 2m band, despite the other HF, UHF, and 50 MHz bands operating correctly. Suspecting an excess of input signal during FT-8 mode transmission, they conducted measurements with an oscilloscope, revealing a burnt-out PIN diode, identified as D3003, type HSU277, on the PA unit board. Following the replacement of this surface-mounted diode, their FT-817 resumed operation on the 144 MHz band.

The DIY Power Meter project utilizes the _INA226_ high-side power monitoring chip, paired with an ATtiny85 microcontroller, to measure voltage, current, and power, displaying the results on a 128x32 OLED screen. The INA226 communicates via an I2C interface and is programmed with a calibration factor based on the shunt resistance and current register LSB. The project is designed to handle a maximum current of 500mA using a 0.16ohm shunt resistor, which can be adjusted to a 0.2ohm resistor, reducing the full-scale current range to 409mA with a resolution of **12.5uA**. The shunt resistor dissipates only 33mW at maximum current, making 1/4 watt resistors suitable for the setup. The PowerMeter.ino sketch configures the shunt resistance and maximum design current, automatically calculating the calibration factor. The project can be prototyped on a breadboard using an Arduino Uno, employing the Wire library for INA226 and OLED communication, and the u8g2lib library for the OLED display. For the ATtiny85 version, the Adafruit-TinyWireM and Tiny4kOLED libraries are used. The power meter is independently powered by a 3V CR2032 cell, with power switching options including manual switches or DC switched jacks. The low-side n-channel MOSFET switch configuration is tested but introduces voltage drop issues, making manual switching a more reliable option until a suitable DC switched jack is found. DXZone Technical Profile: INA226 | ATtiny85 | OLED Display | Power Meter

The article discusses the evolution of antenna designs, specifically focusing on the upgrade from the W7IUV rotatable Flag to the Waller Flag. Author Pierluigi Mansutti IV3PRK shares insights on modeling these antennas using EZNEC software, detailing their performance in noisy environments. The W7IUV Flag proved effective for receiving signals, while the Waller Flag, developed by NX4D and N4IS, offers improved front-to-back ratios but requires careful consideration of signal levels and noise management. The article emphasizes practical modeling results and interactions between different antenna setups.

Moto-QRP setups offer compact, weatherproof QRP transceivers for portable ham radio use, ideal for motorcycle and backpack operations. The YouKits HB1A MKII, a 5W CW rig, is paired with a lightweight long-wire antenna and an Elecraft T1 tuner for efficient field communication. This setup fits in panniers, enabling operators to explore parks and remote locations. Accessories include a durable Morse paddle, FCC documentation, and essential logging tools, making it a perfect choice for adventurous QRP enthusiasts.

Repairing a non-functional Yaesu FT857 by identifying and replacing two damaged components crucial for powering the device. Using discrete components, author constructed replacements for the DAN222 and RT1N241 ICs, successfully restoring the rig's functionality. This DIY approach not only fixed the issue but also provided a satisfying and cost-effective solution

The author fixed a friend's Kenwood TS-850S radio, which suffered from Capacitor Plague, a common problem in 1990s electronics where capacitors leak and damage circuit boards. The CAR board, responsible for generating signals, was especially affected. The author cleaned the board, replaced the capacitors, and repaired a broken trace. Although the radio mostly functioned afterward, the "Slope Tune" control behaved abnormally. The cause seems to be a software issue, not a hardware one.

Information on frequencies suggested as Scout amateur radio frequencies. These were initially suggested by the World Organization of the Scout Movement and their Jamboree on the Air organizer. As with all amateur radio frequencies they are a shared resource. If someone else is already on that frequency, move up or down to find a clear frequency for calling.

The influence of temperature changes in Common Mode Chokes. To get an indication of the impedance behavior when the core temperature changes, the author tested a CMC by heating it with a hairdryer, and measuring its temperature with an infrared thermometer. When the CMC temperature rises from 30C to 90C, the frequency of maximal impedance shifts down from ca.10 MHz to ca.7.2 MHz, or by a factor 1.4.

The article "Icom IC7300 RTC Fix" details the meticulous repair of an Icom IC-7300's faulty real-time clock (RTC). The author and a friend, Nacho, discovered the RTC was gaining an unacceptable 11 seconds per day. Investigations revealed the Seiko Epson RX8803LC RTC was far outside its specified stability. Despite replacing the RTC and a burned pullup resistor, the transceiver still malfunctioned, leading to the replacement of the processor. Post-repair, the clock's accuracy improved significantly, now gaining only 1.4 seconds per month. This narrative underscores the complexities of electronic repairs and the satisfaction of resolving intricate issues.

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 PDF presentation explores using aircraft reflections for VHF communication. It explores the characteristics of reflected signals, including how they cause fading and vary in frequency due to aircraft movement. The feasibility of using such signals for communication is then examined. The presentation highlights challenges like requiring very narrow filters and strong frequency stability. It explores Slow-Feld, a slow version of Hellschreiber, as a potential modulation mode due to its tolerance for weak signals and frequency variations. While successful communication via aircraft reflections has been achieved, the data rate was slow and intermittent. The potential for communication over long distances, especially with busy air traffic, is discussed.

After owning the second-hand radio for a few months, it developed a sense wire failure, limiting output to 20 watts. Yaesu support advised the owner, an Electrical Engineer, to investigate. The issue was traced to a blown digital transistor, Q1032. Yaesu provided free replacements, revealing intricate internal components during the repair.

A web page dedicated to amaterur radio scouting. Scouting and Ham Radio — From Yesterday, Toward Tomorrow. Radio Merit Badge, Morse Code Interpreter Strip, Jamboree on the air

The resource details a novel approach to Morse code (CW) reception for hearing-impaired operators, focusing on a handheld device that translates CW signals into tactile vibrations. It explains how this device allows users to perceive the patterns of dots and dashes through physical feedback from a shaker, addressing the challenges of auditory discrimination for those with hearing loss. The content highlights the potential for this tactile method to aid in CW learning and interpretation, even suggesting benefits for operators with normal hearing by providing an alternative sensory input. The article also mentions the device's _patent-pending_ status and its availability to members of the _Long Island CW Club_ and the general public. It provides contact information for further inquiries about this innovative tool.

Our Article about the ICOM IC-7760 announce done by ICOM at the annual Ham Fair in Tokyo

The TY0RU DXpedition to Benin in 2022 achieved over **100,000 QSOs** from Cotonou, IOTA AF-051, operating across 160m through 6m bands using CW, SSB, and FT8 modes. The operation involved a team of 12 operators, including _F5RAV_, _F4WBN_, and _F1TCV_, utilizing multiple stations with transceivers like the Icom IC-7300 and IC-7610, paired with amplifiers and various antennas such as verticals, dipoles, and a 4-square array for 40m. The expedition's log is available on Club Log, supporting OQRS for both direct and bureau QSLs, with F5RAV serving as the QSL manager. The site details the team's travel, setup, and operational challenges, including local conditions and equipment deployment, offering insights into the logistical complexities of activating a rare DXCC entity. Donors are acknowledged, and a photo gallery documents the activity.

The article by Guy Olinger, K2AV, published in the May/June 2012 National Contest Journal, introduces the Folded Counterpoise (FCP), a compact 516-foot single-wire counterpoise elevated at 8 feet, designed for 160-meter operations on small lots like 100x150-foot backyards. Originating from efforts to revive Top Band for W0UCE on a postage-stamp property, the FCP uses strategic folds to cancel ground fields within 33 feet of center, minimizing losses to 0.13-0.53 dB—outperforming sparse or on-ground radials by up to 15 dB in poor soil—while mimicking opposed radials for efficient feedpoint impedance. Paired with a critical 1:1 or 4:1 isolation transformer (e.g., trifilar on T300-2 toroid) to block common-mode currents on coax feeds, it delivers proven results: K2AV's #8 North America low-power contest score, 7+ dB gains at W4KAZ and K5AF, and over 10,000 global web hits for DIY instructions using bare 12 AWG wire and weatherproof enclosures. Ideal for acreage-challenged hams, the FCP also excels on 80 meters with scaled dimensions, offering a low-loss alternative where full radials are impractical