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This document is a must read for anyone considering building a good low cost HF multi-band antenna system. The author combine in this document four important ingredients to produce simple but effective antenna system, like antennas of non resonant length, line attenuation, the transmatch and the balun

Presents a construction project for a 1:1 current balun, specifically detailing the _Sorbie Balun and Bottle Choke_ design. The resource outlines the winding technique, employing 4+4 turns of mini coaxial cable on a large ferrite core, and provides insights into the physical assembly. It includes specific material recommendations, such as the type of ferrite and coaxial cable, crucial for achieving the desired impedance transformation and common-mode current suppression. The content covers the practical steps involved in building the balun, from preparing the coaxial cable to securing the windings on the ferrite toroid. It also discusses the integration of the balun into an antenna system, emphasizing its role in maintaining pattern integrity and reducing RF interference in the shack. The resource offers a clear, step-by-step approach, making the project accessible for homebrewers. Illustrations and photographs accompany the text, visually guiding the builder through each stage of construction. The article concludes with performance expectations and considerations for deployment, ensuring the constructed balun functions effectively across the intended frequency range.

This resource details the construction of a Moxon rectangle antenna, a two-element wire beam, drawing inspiration from a _QST_ article by Allen Baker, KG4JJH, and a project group led by KD6WD. It outlines the use of _AC6LA_ software for critical measurements (A-E) to design the antenna for specific bands like 17 meters, emphasizing the simplicity of adjusting frequency and wire size. The guide covers material selection for spreaders, such as telescoping fiberglass fishing poles, and various hub constructions, including aluminum tubing and PVC joints, with accompanying images. The author shares practical insights from building multiple Moxons for 10, 15, 17, and 20 meters, noting consistent 1:1 SWR at design frequencies and broadbanded performance. It describes the feedpoint assembly using a 1:1 Yagi current balun and wire nuts for robust, adjustable connections. The resource also discusses element insulators made from Lucite strips and attachment methods to spreaders using plastic wire ties and duct tape, ensuring precise element spacing. Performance observations include significant signal improvements (4-5 S units) over quad loops and a unique "DX-Vane" effect where the suspended antenna self-aligns with the strongest DX signal. The author also recounts an unsuccessful attempt at a dual-band 17/20 meter Moxon, concluding that the Moxon is inherently a monoband antenna, supported by _EZNEC_ plots for a 17-meter design.

This article serves as a beginner-friendly guide to constructing a simple VHF dipole antenna for 2 meters, perfect for novices in the hobby. With an emphasis on affordability and simplicity, it explains the basics without overwhelming technical details. Recommendations for coaxial cable and mounting methods are provided, offering practical solutions for effective communication. By following these instructions, novices can build a functional antenna without breaking the bank.

The W6NL Moxon Yagi is a high-efficiency two-element 40m Yagi that uses cross elements to provide both loading and Moxon coupling, addressing the challenge of deploying a directional antenna on the 40-meter band. This resource details the transformation of a _Cushcraft XM240_ Yagi into this Moxon configuration, replacing the original loading coil LCA sections with four new assemblies. The guide provides comprehensive instructions for building the boom and elements, including specific dimensions for new sections and tee loading elements, along with detailed drawings and a full parts list for the conversion. Performance data indicates the converted antenna achieves **10.73 dBi** gain at 7.050 MHz with 99.5% efficiency and a high front-to-back ratio. The VSWR bandwidth is over **300 kHz**, ensuring good performance across a significant portion of the 40m band. Construction involves reinforcing element sections, attaching tee loading elements with U-bolts, and implementing element guying using materials like _Phillystran_ to manage sag and maintain structural integrity.

Building a Double Extended Zepp Antenna

The page provides detailed instructions on how to build a 60 meter End Fed Half Wave Antenna Tuner, with large pictures and diagrams. It is aimed at amateur radio operators looking to construct their own antennas for the 60 meter band.

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

Constructing a compact directional antenna for the 17-meter band, this resource details the build process for a Moxon rectangle, a two-element Yagi variant with folded-back elements. It covers the antenna's evolution from the _VK2ABQ beam_ and provides specific dimensions for a version built using fishing pole whips. The content includes a discussion of the antenna's radiation pattern, feedpoint impedance, and its inherent front-to-back ratio, which is often superior to a standard two-element Yagi. Practical considerations for element spacing and material choices are also addressed, alongside a visual representation of the antenna's physical layout. Performance data presented includes a comparison showing the Moxon rectangle's **2.5 dB gain** over a half-wave dipole and a front-to-back ratio of **20 dB**. The resource also touches upon the antenna's relatively wide bandwidth for a two-element beam and its suitability for portable operations due to its compact footprint. It offers insights into optimizing the design for specific operating conditions and discusses the advantages of its lower take-off angle compared to omnidirectional wire antennas, making it effective for DX contacts on the 17-meter band.

KB6NU end-fed, half-wave antenna article and project

Constructing a directional antenna for the 6-meter band (50 MHz) can significantly improve signal strength and reduce QRM during local ragchews or **Field Day** operations. This project details the assembly of a Moxon rectangle antenna, known for its compact size and respectable gain, making it a practical choice for portable or fixed station use on the magic band. The design utilizes readily available materials such as 14 AWG copper wire for the radiating elements and PVC pipe for the frame, ensuring an inexpensive build. The article provides specific dimensions and construction steps, allowing radio amateurs to replicate the antenna with confidence. It emphasizes achieving a low **SWR** across a bandwidth exceeding 1 MHz, crucial for efficient power transfer from the transceiver. Performance characteristics include a reported 5.5 dBi gain and a front-to-back ratio of 20 dB, offering effective directivity. The project also highlights the antenna's suitability for Field Day, where quick deployment and reliable performance are paramount for maximizing contacts.

Some notes on double-shielded coaxial cable

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

A 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

If you want to design vertical antennas you can find all theory and formulas used to model a vertical aerial calculating capacitance, reactance, building the inductor and calculating resistances. Includes an excel spreadsheet to calculate efficiency.

The page provides a detailed guide on how to build your own NOAA weather satellite receiving station, covering hardware, antenna, computer setup, and software installation. It offers a straightforward explanation suitable for beginners and serves as an educational project. The content includes step-by-step instructions and tips for observing satellites in the night sky.

An article describing how to homebew a VHF 4 elements Yagi antenna.

An interesting presetnation full of usefull tricks to correctly design and build 23 cm Yagi using simple tools. The basic design of the antenna presented in this document is taken from the original DL6WU Yagi Design published in 1982

Build a directional antenna for the 1.2 GHz band, in 15 minutes

An homemade antenna tuner project that should be small, easy to build and cheap. This automatic antenna tuner can work as locale or as remote. The tuner has EEPROM memory for store settings for faster tunning and four interfaces

SWR analysis of an Alpha-Delta DX-LB Plus antenna, configured as an inverted-V with the apex at 40 feet and ends at 15 feet, reveals specific performance characteristics across the HF spectrum. Measurements were conducted using a RigExpert AA54 antenna analyzer, scanning from 0.100 MHz to 54.000 MHz to capture full-range SWR plots. The antenna exhibits notably narrow bandwidths on 80 meters and 160 meters, attributed to its loading coils, necessitating precise tuning for optimal operation within these bands. Conversely, the Alpha-Delta DX-LB Plus demonstrates excellent SWR across the entire 40-meter band, indicating a broad resonance. Performance on 10 meters also shows favorable SWR, though tuning to a desired operating frequency is still recommended for peak efficiency. The article details the methodology and tools employed, building upon a previous "Part 1" analysis of a G5RV antenna, providing a comparative context for antenna evaluation. Practical experience with this multi-band antenna, particularly its loading coil design, highlights the challenges in achieving desired SWR across all bands without specific adjustments. The author's subsequent plans involve replacing the Alpha-Delta DX-LB Plus with a homebrewed 80-40-20-10m parallel **fan-dipole**, aiming for improved resonant characteristics.

Building a LEO satellite ground station, and eggbeater antenna for the 70cm band

A page dedicated to servicing and building a 10 meter band moxon Antenna

Twenty-four repeaters, including D-STAR and Fusion systems, are maintained and operated by MARCA Inc., primarily located on Arizona mountaintops and around the Phoenix metropolitan area. The organization, holding the callsign _W7MOT_, facilitates a wide range of amateur radio activities, such as ARRL Field Day events near Forest Lakes, Arizona, and participation in ARRL FMT contests. Members engage in antenna experimentation, construction, and maintenance trips to repeater sites. The club's interests span diverse topics, including HF voice, digital modes like _WSPR_, _WSJT-X_ (FT8, FT4), and CW, alongside DXing, MESH networking, and EOC operations. It supports technologies from SDR radio building to antique radio restoration and computer-based operations like Echolink, fostering a Single Board Computer (SBC) and Raspberry Pi group. Monthly meetings, held on the third Tuesday, feature business discussions and guest presentations, with informal summer gatherings and an annual holiday dinner in December. Monthly VE testing sessions for Technician, General, and Extra Class licenses are conducted by Ray Vasquez, K4RMV. Post-meeting discussions often cover specialized interests such as repeater operations, technical topics, D-STAR, SDR, APRS, Fusion, and Raspberry Pi projects.

A home made 4 element yagi antenna that can be easily adapted for 10 meter band

Constructing a dip oscillator provides radio amateurs with a fundamental piece of test equipment for resonant circuit analysis. This particular design, adapted by VK3YE from a concept by _Drew Diamond VK3XU_, details a practical build using readily available components. The unit incorporates four plug-in coils, covering a frequency range from **2.6 MHz to 55 MHz**, mounted on 5-pin DIN plugs for versatility. A salvaged two-gang air dielectric variable capacitor, fitted with a vernier reduction drive, serves as the tuning mechanism, with the smaller gang optimizing bandspread at higher frequencies. In practical application, the dip oscillator is used by setting the meter needle to approximately two-thirds scale. When the instrument's coil is brought near a tuned circuit under test, a noticeable dip in the meter reading indicates resonance. This allows for precise measurement of resonant frequencies in antennas, filters, and other RF circuitry, proving invaluable for homebrewing and troubleshooting. The design emphasizes short wire runs for stable operation, particularly at the higher end of its operational range.

Building an omnidirectionnal antenna for the 23 cm band

1500 watts PEP SSB is the power handling capability of the MFJ-989C HF Antenna Tuner, a popular choice among amateur radio operators. Users have shared a wide range of experiences, with some praising its durability and performance over decades of use, while others criticize its build quality and accuracy. The tuner features a built-in dummy load, SWR-wattmeter, and a balun for balanced line feeders, making it versatile for various antenna setups. However, discrepancies in RF power readings and SWR measurements have been noted, with some users finding the dual scale meter to be off by about 20% compared to a Bird wattmeter. Long-term users report that the MFJ-989C performs well with proper antenna setups, but caution against tuning at high power without initial adjustments at lower power levels. Some have experienced issues such as arcing when exceeding 400 watts, while others have had no problems even at higher power levels. The roller inductor and capacitors are functional, though some users have had to perform maintenance like tightening screws or cleaning components to ensure reliable operation. Despite mixed reviews, the MFJ-989C remains in production, suggesting continued demand. It's a tuner that requires careful handling and possibly some DIY fixes to achieve optimal performance.

Examines Radio Frequency Systems (RFS), a manufacturer specializing in high-performance cable solutions for diverse communication infrastructures. The company, with over 120 years of heritage, focuses on designing and producing robust, long-life connectivity systems, including _low loss foam dielectric RF cable_ and _premium radiating cable_. RFS's product range supports critical applications in cellular networks, microwave antenna systems, and specialized installations within buildings and tunnels. The resource highlights RFS's commitment to innovation, addressing emerging industry standards like _FRMCS_ for railway communication and advanced fiber solutions for data centers. It also details the company's manufacturing capabilities in Hannover, Germany, emphasizing the quality and reliability associated with _Made in Germany_ products. The content covers various connectivity landscapes, from urban solutions for connected cities to private 5G credentials and future plans. Specific product categories include _fiber, power & hybrid cable_, and _low loss high power air dielectric RF cable_, showcasing their broad portfolio for complex RF environments.

Full article on how to build a home-made wire dipole antenna for 40 and 80 meters band. Article is fully in italian, as it was published on ARI RadioRivista, but is plenty of self explaining pictures that will guide you on homebrewing this trapped dipole antenna for the lower amateur radio bands.

If you like building good antennas, this one is for you. The J-pole is a slim, omnidirectional, half-wave antenna fed at the end through a quarter-wave shorted transmission line. Its predecessor is the famous Zepp antenna developed for the Zeppelin airship.

Selecting appropriate coaxial cable and wire for demanding amateur radio applications, particularly those involving high power or harsh environmental conditions, is crucial for maintaining signal integrity and operational safety. This resource details Harbour Industries' specialized offerings, which include Mil-Spec and commercial designs such as NEMA HP3/HP4 and SAE AS22759, suitable for aerospace, military, and industrial sectors. Their product line addresses the need for robust conductors capable of withstanding extreme temperatures and mechanical stress, often encountered in antenna systems or amplifier interconnections. The company highlights its AeroPOWER® Firezone M25038/3 cable, specifically engineered for high-temperature environments like aircraft engines. This particular product exemplifies their focus on solutions for critical infrastructure where reliability under adverse conditions is paramount. Such cables are relevant for hams building or maintaining stations in challenging climates or those operating high-power amplifiers where internal wiring must endure significant thermal loads. Harbour Industries also provides a range of high-performance cables designed to meet stringent specifications. Their expertise in high-temperature and high-performance cable manufacturing positions them as a supplier for specialized wiring needs beyond standard off-the-shelf options, ensuring durability and performance for advanced amateur radio setups.

Utility-Driven Tradeoff Analysis, if you want to geto on the microwave bands , you will have to choose the proper antenna for your operating conditions. How to decide is not always easy, and you may also decide to build your own antenna.

9M6MU Alfons details his family's efforts to establish an independent, self-sufficient home at Eagle Plateau in Borneo, a 50-acre highland property. The resource highlights their integration of **solar photovoltaic panels** for power generation, alongside managing water supplies, organic gardens, and fruit trees. It covers the practical challenges and rewards of living off-grid, including maintaining power generators and addressing infrastructure needs, all while pursuing the hobby of amateur radio. The narrative emphasizes a holistic approach to healthy living and nature conservation, reflecting the family's aspirations for an ideal ham world. Alfons and his XYL Doris share their experiences in building shelter and antenna farms, showcasing their dedication to independence and sustainable practices away from the conventional grid. The site also references the Hillview Gardens Amateur Radio Club, suggesting community involvement.

Experimenting a 20 40 meter short coil loaded dipole antenna with the goal to keep the total length under 40 feet so that the dipole can be mounted on two 20 foot fiberglass pole to make a 20/40 meter rotatable dipole.

A light and sturdy Quad for 10 and 15 meters. Basic Quad antenna design considerations. Building and assembling a dual band HF QUAD antenna, designing and joining cross-arms and boom, assembling spreader and element wire installation notes. QST article.

Building an amateur station for competitive radiosport involves a number of critical steps, regardless of the band or bands you focus on. These include, but are certainly not limited to: Station layout, Equipment interconnection and switching, Inter-station interference, Antenna selection. Radio interface with the logging program, CW and voice keyer integration, Rotator control

A very well done presentation about End-Fed Half-Wave antennas. This PDF document contains a summary of experiences in how to build custom EFHW antennas. Includes an interesting comparison table of UnUn configurations with recommended toroids, Wire size, turns and capacitors. An useful recap on common errors in building homebrew EFHW Ununs completes the document.

The standard J-Pole antenna is a end fed 1/2 wavelength antenna, in this article is explained also how to build an expanded Super J Pole that provides about 4.5 dbd gain. These antennas can be built from EMT electric conduit pipe

An experimental prototype of an asymmetrical hatted vertical dipole antenna that can work on HF bands 20 to 10 meters band. The AHVD Vertical dipole is an upside-down T design

Constructing a multi-band fan dipole for HF operation presents unique challenges, as VE2XIP demonstrates through his 2012 project to replace an existing commercial antenna. He details the process of calculating wire lengths using the 468/frequency formula, emphasizing the critical importance of equal leg lengths for each dipole element. The author shares practical insights gained from building at ground level, noting how elevation impacts resonant frequency and SWR, particularly for lower and higher bands. VE2XIP's experience highlights the iterative nature of antenna tuning, starting with the lowest frequency band (80m) and working upwards. He provides a specific example of trimming calculations and offers a clever tip for accurate wire removal. The article also touches on the mechanical aspects, such as dowel spacing for wire support and the benefits of a pulley system for repeated raising and lowering during the tuning process. Field results showed significant performance gains over the previous Alpha-Delta DX LB Plus, with **20 dB over 9** signal reports on 80m compared to 57. The project cost around **$100** for hardware, proving a cost-effective alternative. The author also discovered a bonus 6m capability and achieved an inverted-V _obtuse angle_ of approximately 115 degrees, contributing to a surprisingly stealthy installation.

Comprod Communications specializes in the design and manufacturing of RF communication solutions, including a comprehensive range of antennas, duplexers, multicouplers, and combiners. The resource details their product categories, which encompass base station antennas, mobile antennas, transit antennas, and disguised antennas, alongside mounting solutions and in-building systems. It highlights the company's 40-year history in adapting offerings to client needs and anticipating industry trends, emphasizing product durability and low maintenance for harsh environments. The company's offerings are presented as high-quality, designed to withstand extreme conditions from Arctic cold to equatorial heat and humidity. The site mentions solutions and technical sales support, training, and site analysis and system design as part of their service portfolio. It also references being a market leader trusted by over 1,000 customers worldwide, positioning itself as a partner for RF communication needs.

Build a SPDT coaxial relay that can be used as a main Transmit/Receive relay or an A-B switch to select between two different 6m antennas

A practical guide on hombrewing Yagi antennas, including notes on Driven Element, Transformation & Symmetrising Coax Lines, Full Boom length vs. electrical length, Elements & Insulators on Boom and additional tips and tricks, in English and German

Useful tips on building cobweb antennas. Since I've done so many posts on the Cobweb antennas I thought it best to separate them on a different page so that potential Cobweb builders can see all the posts together. Hopefully this will make planning and building easier.

RSGB article for beginners. How to build a dipole antenna, construction tips and correct setup of inverted-ve dipole antennas

Building the Three-Element Hex Beam. A project and construction phase of an HF hex-Beam antenna using trees to hang the antenna and a Channel Master antenna rotator.

Presents an alternative construction method for isolated element Yagi antennas, specifically for VHF/UHF operation. The technique utilizes commercially available vibration damping clamps (resin support blocks) to isolate 1/4-inch aluminum rod elements from a 1-inch square aluminum boom, simplifying the build process by eliminating the need for custom-machined insulators. This approach is demonstrated through the construction of 6-element Optimized Wide-Band (OWA) Yagis for the 2-meter, 1.25-meter, and 70-centimeter bands, which are well-suited for portable contesting arrays due to their light weight and decent gain. The document provides detailed specifications for element and boom materials, along with step-by-step procedures for cutting, drilling, and tapping. It also covers the fabrication of a feedpoint bracket for a direct 50-ohm SO-239 coax connection and discusses considerations for horizontal versus vertical polarization, including mast placement. The resulting 6-element models achieve an average free-space gain of 10.2 dBi and a 25 dB front-to-back ratio, with the construction technique being scalable for higher gain designs. Included are parts lists with sources, detailed mechanical drawings for each band, and EZNEC data for the 2-meter and 70-centimeter designs, showing both free-space and 30-foot elevation performance. The designs are optimized from W4RNL's original concepts using HAMCALC, ensuring good gain, passband characteristics, and front-to-back ratios for wideband Yagi operation.

The Cambridge University Wireless Society (CUWS) serves as the amateur radio society for students and staff at Cambridge and Anglia Ruskin Universities, fostering interest and activity in two-way radio communication. It provides a platform for members to engage with various aspects of amateur radio, including operating, technical experimentation, and community building within the university environment. The society's activities typically encompass station operation, antenna construction, and participation in contests and DXing. As a university-affiliated club, CUWS offers practical experience in radio theory and application, often utilizing the club callsign _G6UW_. Members learn about different modes of operation, such as CW, SSB, and digital modes, and gain hands-on experience with transceivers and associated equipment. The society's focus includes preparing members for amateur radio licensing exams and promoting ethical operating practices. Participation in CUWS provides a foundation for future involvement in the broader amateur radio community.