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The Shrunken Quad antenna is a unique design that offers full-sized performance on the 10m and 15m bands while incorporating linear loading via a trap for operation on the 20m band. This design allows for effective communication in the HF spectrum, making it suitable for both casual operators and serious DXers. The quad configuration provides excellent gain and directivity, which is beneficial for contesting and long-distance contacts. Constructing the Shrunken Quad involves careful attention to dimensions and materials to ensure optimal performance. The antenna's compact nature makes it an excellent choice for limited space situations, allowing operators to enjoy the benefits of a quad without the need for extensive real estate. This project is ideal for amateur radio enthusiasts looking to enhance their station's capabilities with a versatile and efficient antenna system.

This DIY Yagi costs less than 20 Dollars, and let you increase the performance of your connection. With this project you can build a better Yagi beam antenna resonant on 850MHz, a 8 element yagi directional antenna

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.

This blog post documents the author's journey building an APRS micromodem for amateur radio applications. Using an open-source design by LY2EN, the author assembled a cost-effective Terminal Node Controller (TNC) with SMD components, an Arduino Nano, and a JDY-31 Bluetooth module. The construction process included PCB fabrication, careful component soldering, microcontroller programming, and Bluetooth configuration. A custom 3D-printed case protected the completed device. Field testing in Romania showed the device functioned with a Baofeng UV-5R radio, though antenna limitations affected performance. The entire project demonstrates an affordable DIY alternative to commercial APRS trackers.

This page delves into the debate surrounding the End-Fed Half-Wave (EFHW) antenna, exploring whether it is truly a multiband antenna without the need for a tuner. The author investigates the claims and criticisms surrounding these popular antennas, discussing their resonance on various bands and their efficiency for DXCC achievements. The content is valuable for hams interested in understanding the capabilities of EFHW antennas and their performance across different HF bands, with a focus on practical usage and real-world results.

The PicoFox is a versatile fox transmitter for 2-meter ham radio operators, built around the RP2040 microcontroller. With open-source hardware and software, it can be customized to suit your needs, from APRS to other digital modes. This fully assembled transmitter comes with a rechargeable battery and antenna, ready for use. The design allows for easy addition of features like sensors or interactivity. Modulation is handled in software for smooth FM output, with ample CPU, flash, and GPIO available. Configure your PicoFox by connecting it to a computer via USB and adjusting settings in a text file. Explore the possibilities of this innovative transmitter for your amateur radio projects.

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.

This presentation on antennas is a practical guide for amateur radio operators. The key takeaway is that the best antenna for your station depends on your constraints and goals. There is no magic solution and buying a wire antenna is not recommended as it might be expensive and not as effective. The presentation covers different antenna types including dipoles, verticals, Yagis and loop antennas. Important factors to consider when choosing an antenna include SWR, feeder types, and whether you need a balun. The author emphasizes that ATUs don’t improve a poor antenna and advises against obsessing over SWR readings.

This article details the development of an 80-meter antenna within the confines of a restrictive covenant community. Faced with limited space, the author explores various options before implementing a clever hybrid design: a short 30-foot vertical wire running discreetly down the building's exterior combined with a capacitive top hat installed in the attic. Computer modeling confirmed the superiority of capacitive loading over inductive loading, increasing radiation resistance from 6 to 14 ohms. The perimeter wire top hat, naturally supported by the attic structure, resonates effectively at 3.5 MHz. The system is completed with four buried 60-foot radials installed "after dark" to maintain compliance with community restrictions.

This article focus on the radiation angle of vertical antennas and the fundamentals of electromagnetic wave propagation. The calculation of antenna length at 145 MHz is followed by an explanation of electromagnetic wave speed and the link between wavelength, frequency, and velocity. Author discusses the 5/8th wave vertical antenna, namely its performance and the influence of radiation angle on signal transmission. Figures and analogies demonstrate how different antenna types produce distinct radiation patterns. This highlights the importance of selecting the right antenna for a certain purpose, such as local traffic or dxing. The article discusses a variety of factors that affect antenna performance, including SWR, propagation conditions, and equipment dependability

AutoEZ, Automated use of EZNEC, is an Excel workbook that works alongside EZNEC antenna modeling software version 5.0 or later. With AutoEZ, you can control different aspects of your model using variables and run multiple EZNEC test cases automatically. Formulas in Excel allow you to modify any part of the model. AutoEZ's interface resembles EZNEC's. Enabling macros in Excel might be necessary before using AutoEZ. The program opens various model file formats including EZNEC (.ez), NEC (.nec or .inp), AO and NEC/Wires (.ant), and MMANA-GAL (.maa). You can set the frequency and/or variable values for the test cases to be run through EZNEC. AutoEZ allows you to create animations showcasing how the pattern changes as the model configuration is modified. You can download a fully working, but limited demo copy from this site.

Learn how to choose the right portable antennas for backpacking as a ham radio operator. Find out the factors to consider, including weight, performance, and reliability. Understand the trade-offs involved in selecting the best antenna for your needs, based on the purpose of your trip and distance to be covered. Discover different options available and how they can help you make contacts while on the go. Get insights into one ham radio operator's portable antenna kit and the factors that influenced their choices. Explore the importance of band selection and adaptability in creating a successful antenna system for backpacking adventures.

A cost-effective alternative to the Optibeam OB10-3W, a high-performance but expensive tri-band Yagi antenna for the 20, 17, and 15-meter bands. The original Optibeam, featuring three full-size elements on each band, delivers strong forward gain and front-to-back ratio but comes with a high price tag. To address this, a custom design was developed, offering similar performance at a fraction of the cost. Using accessible materials and a simple 1:1 current balun, the homemade version proved highly effective, making it a practical solution.

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.

Provides a comprehensive overview of the Hentenna design, construction methods using aluminum tubing, and discusses its bidirectional characteristics with illustrative photos

Learn how to construct a balanced Antenna Tuning Unit (ATU) for your ham radio equipment. Follow the instructions provided by Bengt, SM6APQ, to create a variable capacitor insulated from the ground for additional safety. Discover how to set up the ATU for the 20 to 10m band with proper spacing between coils. Use low power when adjusting the ATU for lowest SWR. Avoid using switches and opt for banana plugs for flexible connections. Visit the Creative Science Centre website for more information and resources on ATU construction.

Focusing on the Indian amateur radio community, this resource provides a collection of articles covering news, technical tutorials, and DIY project instructions. It features content on various aspects of ham radio, including club activities, circuit ideas, and general information relevant to operators in India, often referencing local events and regulations. The site serves as a central point for information exchange within the region. The author, VU3HZW, shares insights and practical guidance, drawing from personal experience to present topics such as antenna construction and station setup. The content aims to support both new and experienced hams, with articles detailing specific projects and offering practical advice for improving station performance or engaging in local ham radio activities. For instance, one article might detail a simple _QRP transceiver_ build, while another could discuss optimal antenna placement for **local nets**.

This article is from the book Ham Radio For Dummies and features some tips for portable amateur radio operations, on Field Day or generic outdoor operation, like selecting the proper antenna and portable power.

In this article, VE9KK discusses the various restrictions faced by ham radio operators when it comes to setting up antennas. The author shares personal experiences and tips on how to overcome these challenges, providing valuable insights for fellow hams. Whether you're dealing with space limitations or neighborhood regulations, this resource offers practical solutions to help you get the most out of your ham radio setup.

A project for a six meters Yagi beam antenna, built mainly for portable operations. This is a 4 element Yagi beam with a 4 meters boom.

Kanga Products offers a diverse range of kits and pre-built items for amateur radio operators, including Morse tutors, keys, antenna tuners, and dummy loads. Their products cater to both beginners and advanced users, with options for practice oscillators, receivers, and various electronic components. The company provides detailed instructions and supports DIY projects, making it a go-to for hobbyists seeking practical and educational tools.

This page discusses the purchase of a fiberglass push-up mast for portable operations in the ham radio hobby. The author shares their experience with the MaxGain Systems MK-4-HD mast, highlighting its versatility for both home and on-the-go setups. They also detail modifications made to the mast base and provide insights on tube sizes for different antenna types. The content is useful for hams looking to improve their portable station setup and optimize antenna performance in various environments.

This article published on QEX details measurements of tree conductivity and permittivity at HF frequencies, addressing a long-debated topic in amateur radio. N6LF conducted experimental impedance measurements on Douglas fir and maple trees using a vector network analyzer with rings of nails inserted into tree trunks. Results showed that tree conductivity increases with frequency while relative permittivity decreases, similar to soil characteristics. Measured conductivity ranged from 0.06 to 0.4 S/m at 10 MHz, aligning with values used in previous research. These findings validate that NEC modeling can reliably estimate trees' substantial impact on HF antenna performance.

The Beverage on Ground (BOG) antenna offers ham radio operators a compact alternative to traditional Beverage antennas, requiring less space and fewer support structures. This implementation, optimized for 1.8-7 MHz bands, describes ideal parameters: lengths of 60-90 meters, height of 2-10 cm above ground, and specific load resistances based on configuration. The article details experimental methods for determining optimal load resistance and presents matching systems to convert BOG impedance to 50 ohms. While less effective than classic 200-300 meter Beverages, the BOG provides directional reception in limited space, though performance varies with ground conditions and weather changes.

Paul McMahon details the design and construction of a four-element Yagi antenna for the 50-52.5 MHz range, published in Amateur Radio Magazine (Dec 2011). The antenna, featuring a raised driven element and a capacitive/DC connection using copper strips, maintains consistent VSWR and performance despite two years of weather exposure. The design utilizes inexpensive plumbing conduit for the boom and provides detailed construction guidelines, parts lists, and performance analysis through 4NEC2 simulations.

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.

The resource details the construction of a 433 MHz LoRa APRS iGate and a tracker, both built around _TTGO T-Beam v1.1_ microcontroller boards. Each board integrates an OLED screen, WiFi, GPS, and an SMA antenna connector, powered by an 18650 3.7 V lithium-ion battery or microUSB. The iGate operates on 433.775 MHz, with its status verifiable on aprs.fi, demonstrating practical implementation of LoRa-based APRS solutions. The methodology involves programming the modules using Visual Studio Code with the PlatformIO plugin. This process loads the necessary firmware and a JSON configuration file, which includes the operator's callsign and WiFi credentials for the iGate. The guide emphasizes the ease of programming and provides specific steps for configuration. Initial testing of the iGate and tracker, including smart beaconing configuration, is documented. The low power output of approximately 200 mW from the LoRa board's transmitter is noted, with suggestions for range extension through improved antennas or RF amplification. The author, N4MI, plans to deploy a higher-gain 70cm antenna for the iGate.

This page provides information and links about Quadrifilar Helix Antennas, the best antenna for APT satellite reception. It explains the basic design and configuration of QHA, including the research and developments that have been made over the years. The page offers insights into the radiation patterns and benefits of using QHA for APT ground stations, with examples of polar diagrams. If you are interested in learning more about QHA and its applications, this page is a valuable resource.

With increased ES propagation, this lightweight 5-element LFA antenna offers enhanced performance over the Bigwheel antenna's 5dBi gain, delivering approximately 11dBi and forward gain. Designed from G0KSC’s specifications, the 1.8m antenna was adapted for reduced weight using 6mm and 4mm rods instead of heavier tubes. 3D-printed PETG clamps ensure durability and precision, while the first tests showed excellent SWR and element coupling. Though built with a temporary Choke BalUn, the results were promising, with a Pawsey Stub BalUn planned next for further optimization.

Discover the secrets of Six Meters with this comprehensive eBook by Jim Wilson, K5ND. Learn about the magic of 6-meter DXing, including propagation, antennas, equipment, operating software, and more. Whether you're a beginner or an experienced ham radio operator, this book covers everything you need to know. With over 8,000 downloads, this updated version includes new chapters on FT8/FT4, MSK144, and Q65 modes, as well as contesting, rover operation, and awards. Get your hands on this valuable resource and enhance your 6-meter DXing experience today.

Learn how to build a simple transmitter called the 'Easy Ten' that can be easily heard at a distance of 10 miles using a random length wire antenna thrown into a tree. This article focuses on working with frequencies in the 3.5 and 7 MHz range without the need for complex setups like coax lines or baluns. The author shares their experience of making contacts across the Pacific Ocean and the United States using just one watt of output power and simple antennas. Discover how to optimize signal output using a homemade level meter made from a DC microameter and a germanium diode.

A 13-foot total radiating element length is achieved by combining a Buddipole Long Telescopic Whip with 4 feet of modified tripod tubes, forming a low-profile, multiband antenna for **POTA** operations. The resource details the transformation of an Amazon Basics Aluminum Light Photography Tripod Stand, focusing on electrically isolating the top two radiating sections from the bottom support. John, VA3KOT, outlines component sourcing, including the 9-foot 4-inch fully extended whip, and emphasizes using adhesive copper tape for reliable electrical contact and conductive grease to prevent oxidation at tube connections. The construction process, while not requiring specialized tools, highlights careful assembly to ensure proper electrical conductivity and mechanical stability. The author's experience with this setup suggests its effectiveness for portable activations, offering a discreet profile compared to larger antenna systems. The design prioritizes ease of deployment and transport, making it a practical solution for operators seeking a compact yet versatile antenna for field use.

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 behavior of a straight dipole and its L-form is examined in terms of impedance and SWR. By adjusting the feed point or bending angle, impedance variation is observed. Impedance shifts symmetrically as the feed point deviates, leading to recommendations for optimal ratios. Model simulations aid in understanding and fine-tuning, crucial for achieving a 50 Ohm match. Practical tuning guidelines ensure efficient antenna performance.

Chavdar Levkov, LZ1AQ, presents an experimental comparison of small wideband magnetic loops, building on his previous work on wideband active small magnetic loop antennas. His research focuses on increasing loop sensitivity by maximizing the short-circuit current, which is directly tied to the "loop factor" M = A/L, where A is the equivalent loop area and L is its inductance. Levkov's methodology involves reducing inductance and increasing area through parallel or coplanar crossed (CC) configurations, comparing these designs against a reference single quad loop of 1 m2 area. Experimental verification included testing three distinct loop types: a simple quad loop, two coplanar crossed (CC) loops, and eight parallel loops, all designed to have a total geometric area of 1 m2. Measurements were conducted at 1.8, 3.5, 7, and 10 MHz using a small transmitter 270 meters away, with a Perseus direct sampling receiver for precise signal level assessment. The results consistently showed that CC loops, particularly Loop 5 (two CC circular loops with 1.44 m2 total area), yielded significantly higher currents, up to 9.1 dB over the reference loop at 3.5 MHz, validating M as a reliable predictor of loop sensitivity. Numerical simulations using MMANA further corroborated the experimental findings, demonstrating an almost perfect correlation between the calculated M factor and the induced loop current for 15 different loop models. Levkov concludes that CC loops offer superior sensitivity for a given loop area, while parallel loops are advantageous for minimizing physical volume. Practical recommendations suggest using loops with an M factor greater than 0.5 uA/pT for quiet rural environments, and he provides a spreadsheet tool, WLoop_calc.xls, to aid in optimizing loop configurations for specific operational needs.

G6HKS Yagi Kits & Parts provides material kits for building high-performance PowAbeam Antennas, ideal for VHF/UHF enthusiasts interested in DXing. The kits feature advanced Yagi designs, including the unique ParAclip system, ensuring exceptional all-weather stability and minimizing detuning effects. With resources, tips, and support, the site aims to make antenna construction straightforward for amateur radio operators. The focus is on delivering top-tier performance at competitive prices, empowering users to build and enjoy their own high-quality antennas.

Have you missed pileups where you can feel really important again? Or perhaps you wanted to win a contest from a place where every QSO counts double points comparing to your home country? Or perhaps you wanted to have a relaxed time with a radio shack in a subtropical place? All the above is available and waiting for you to be explored. Warm weather, blue water sea, a radio shack with good antennas….Is that what every DX-er dream about?

Learn how an experienced ham radio operator rebuilt his trap dipole antenna for 30, 40, and 80 meters after a storm damage. Discover the process of upgrading to a short trap dipole for 40, 80, and 160 meters using double-wound traps made from RG-58 coax. Follow along for construction details and tips on building this unique classi.

In his POTA activation, WK4DS experimented with radials for hamstick antennas. Despite sun and RF noise challenges, successful connections were made. Surprisingly, tuned radials proved unnecessary, simplifying setup. Hamsticks demonstrated versatility across frequencies. Increased power improved signal quality, sparking his curiosity for further exploration in radio technology.

This loop antenna is intended to be connected as an antenna for receivers that do not have a built-in antenna such as an HF set or an old tube radio. This square barrel is wound on a wooden frame. It consists of two windings that are galvanically isolated from each other, a main and a coupling winding. The diameter is about 40 cm.

This article presents a novel Top Loaded End-Fed Half-Wave (TLEFHW) antenna design for 20-meter ham radio operation. The antenna features a compact 14-foot vertical radiator with a capacitance hat configuration, eliminating the need for radials or ground systems. Using EZNEC modeling and field testing, the design achieves a 1.5:1 SWR across the 20m band with a 4.11 dBi gain. Key features include quick deployment, lightweight construction, and directional radiation pattern with 110-degree beamwidth. The design, while requiring a 45-foot footprint due to the top hat, offers an effective portable solution for amateur radio operators seeking a no-ground, no-tuner 20m antenna option.

Effective suppression of harmonics and parasitic radiation from HF transmitters is crucial, especially with the increasing sensitivity of VHF/UHF radio channels to interference. This project details a hybrid low-pass filter (LPF) designed to operate across the HF bands up to 51 MHz, making it suitable for 6-meter band operations while providing deep VHF/UHF suppression. The design addresses the challenge of modern interference landscapes, where even microvolt-level signals can disrupt wireless sensors and other simple VHF/UHF receivers. The filter utilizes a single elliptic link, combining high cutoff steepness with robust suppression in the hundreds of megahertz range. A key feature is the use of only two standard capacitor values, simplifying construction and component sourcing. The article provides a detailed schematic, performance characteristics, and _RFSim99_ model file, demonstrating a reflection coefficient S11 below 0.017 (VSWR < 1.03) across 1-51 MHz, ensuring minimal degradation to the antenna system. Construction notes include coil winding specifications and capacitor selection guidance, with recommendations for _FR-4_ assembly. Two capacitor sets are presented, with the first variant recommended for its lower RF current demands, keeping currents below 3 A at 1 kW passing power at 51 MHz. Fine-tuning involves adjusting frameless coils, with considerations for capacitor tolerance and high-frequency capacitance measurement accuracy.

Alan (W2AEW) shares his comprehensive portable field radio kit, showcasing various antenna options and accessories for POTA activations. The kit, housed in a repurposed camera bag, features the Elecraft KX2 Shack a Box, AX1 antenna kit, and additional accessories. With thoughtful organization and adaptability, the kit offers flexibility for different deployment scenarios, ensuring efficient operation in diverse field conditions

Antenna modeling is an essential technique for both amateur and professional engineers, enabling precise analysis of antenna performance. This guide, published on 4 different QST articles by L. B. Cebik, introduces NEC-2, a widely used public domain software for modeling antennas, focusing on its capabilities and practical applications. The series aims to demystify the modeling process, providing foundational knowledge and techniques for effective antenna design. Key concepts include understanding the method of moments and the importance of segmenting antenna elements. By mastering these principles, users can enhance their comprehension of antenna behavior and optimize their designs for improved performance.

The LKJ Wednesday Night Special Antenna, designed by John Whiteman K5LKJ, is a compact 50-foot coil-loaded dipole for 80-meter operation, ideal for space-limited hams in residential areas. Using two 1-inch diameter PVC coils with 87 turns of #16 magnet wire each—placed 10 feet from the center—it tunes to 3.910 MHz for local nets like BVARC Rag Chew. Constructed with #14 wire, ceramic insulators, and Mini-8X feedline, it handles 1000W, performs well at low heights for NVIS, and requires a tuner for bandwidth. Collaborative tuning by club members ensured success.

Compare the efficiency of two HF (or VHF) antennas by simultaneously transmitting FT8 on nearly the same frequency and analyzing PSKReporter SNR data. Determine the effectiveness of your new antenna compared to the old one in dB, to several decimal places. Run FT8 on two transmitters with different call signs and equal power, connected to each antenna. AntennaCompare analyzes global signal reports, isolating antenna performance.

The document provides fundamental information on radio wave propagation and NVIS communication, covering line of sight, surface waves, and ionospheric reflection.<p> It focuses on the Near Vertical Incidence Skywave (NVIS) method for reliable coverage in mountainous or skip zones, especially for regional and emergency communications.

A custom center hub for a Spiderbeam yagi antenna, enabling side-mounting on an existing mast. Challenges included structural instability, limited reach for assembly, and interference with a pre-mounted Spiderpole. A new hub using 40x40mm aluminum tubing provided strength, allowed side assembly, and supported fiberglass pole guy lines. The solution facilitated efficient installation and removal, delivering excellent performance compared to a SteppIR yagi.

Volda is specialized in telecom tower antenna line accessories such as cable hangers, coaxial jumpers, grounding buss bar kits, pole clamps.