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The structure of this dual band VHF UHF antenna is very simple. It consists of two identical square loops, whose sides measure a quarter wave, connected together at the ends. A project by I5NZR

Basic magnetic loop antenna examples and loop aerials theory explained. This article inclued some interesting tricks on building magnetic loop antennas and an usefull excell sheet to help compute magneti loop antennas calculating power efficiency from 10 to 40 meters band

A portable setup of the ICOM IC-705 with portable VHF UHF and and HF Alex Loop antenna, managed with a portable Raspberry PI 3 setup.

Amateur radio loop antenna project using a Comet CVBA-500BC vacuum variable capacitor.

A Shielded Low Frequency Loop Antenna, allows Simultaneous Transmission and Reception at the Same Site.

The magnetic loop, thus named by the use of the magnetic component of the electromagnetic field, is a parallel circuit LC. In this article a sample project to home made a custom antenna. The circular form is often met on the commercial models but this antenna can be hexagonal, octagonal or square.

Building A Full-Wave Quad Loop Antenna for 6 Meters. This is an easy antenna to build and the materials cost about $15-20. It exhibits 1.8dB gain over a 1/2-wave dipole. Using an open-wire parallel feedline (commonly called ladder line) with an antenna tuner, it tunes up on the 10m band as a 5/8-wave loop as well

Fractional Wave Loops antennas are a sort of magnetic loop antennas that differs in several aspects from the standard ones. Author is now SK however in his page he posted several examples and interesting links

A light portable 2 element Delta beam antenna for 14 MHz. It is basically a two element delta loop wire antenna made for portable usage providing good directivity and a 4.2 dBd gain

When experimenting with the WellGood Loop antenna, I came across the PA0RDT MiniWhip design referenced in several places. The construction of the PA0RDT MiniWhip is simpler than the WellGood Loop since there are no inductors to wind, but during my testing, I have found the loop to have slightly better performance.

This active antenna for the shortwave band provides surprising performance, even indoors. As the name implies, the main loop is made from a Hula-Hoop with the metallic paint stripped off and a single turn of 14AWG copper wire inserted inside the hoop.

DL7JV shares his practical experience building and testing capacitive antennas, initially skeptical of their performance compared to magnetic loops and mono-band dipoles. His interest was piqued after hearing a Spanish station running 100 Watts on 80 meters with a 1-meter Micro Vert, making DX contacts into PY and UA0, despite the antenna being only 4 meters high in a garden. This prompted DL7JV to investigate further, consulting resources from DL7PE and DL7AHW, the latter providing DOS programs like "Mitspule.exe" and "Spulenprg.zip" for calculating antenna dimensions and coil conversions. The article outlines the construction of two prototype antennas: one for 7.050 MHz using a 75mm PVC pipe and another for 3.550 MHz with a 110mm PVC pipe. Both designs feature aluminum foil condensers and coils wound from 1mm² H07V-K wire. DL7JV provides specific measurements for the condenser capacitance, surface area, diameter, height, coil inductance, turns, and wire length for both 40m and 80m versions, along with RG58 feedline lengths. Initial reception tests for the 7 MHz antenna, placed indoors, yielded impressive S9+5 signals from a German station compared to an S8 from a 42-meter roof-mounted loop, even hearing a Japanese station. Transmission attempts on April 4, 2004, despite moderate solar storm conditions, resulted in successful QSOs on 7 MHz with EA5OT (579/559) and on 3.5 MHz with YT1NT (579/559) and G4KKI (579/559) using 100 Watts. DL7JV notes the antenna's sensitivity to coordination and feedline layout, suggesting a modification from DL7AXO involving a 500pF fixed capacitor and coil tap for improved SWR stability. He concludes that while the capacitive antenna is space-saving and performs well for reception and 100W transmission indoors, its transmit performance doesn't yet match larger antennas, with further outdoor field tests planned. DL7JV also intends to build a 1.8 MHz version.

This tutorial provides detailed instructions for constructing a DIY magnetic loop antenna, ideal for amateur radio operators seeking efficient short wave communication. The design features a remote tuning system utilizing an Arduino and RC servo, making it suitable for indoor use where larger antennas cannot be installed. Magnetic loop antennas are compact and can operate effectively in confined spaces, but they do require careful handling due to the high voltages and currents they generate during operation. Users should possess the necessary technical skills to implement this project safely. The tutorial includes a comprehensive overview of the antenna's theory, specifications, and mechanical design. It outlines the components needed, including a Soviet-made variable capacitor and a digital RC servo for tuning. Safety precautions are emphasized, as the antenna can produce several kilovolts of voltage and high currents. The project is not certified for safety, and users are advised to proceed at their own risk. The tutorial also provides diagrams and explanations of the antenna's operation, making it a valuable resource for both beginners and experienced operators looking to enhance their setup.

Handmade drawing of a 3 bands single loop, portable quad antenna used by the author during his dx pedition in Kenya as 5H3FM. This antenna is done using 3 telescopic spreaders and the spreader kit for 1 element quad by spiderbeam.

This page by Keith Greiner describes a magnetic loop antenna project, providing step-by-step instructions to create two versions of a system with one large loop and one small loop. It includes details on how to construct the loops using different materials, along with the necessary equipment like antenna analyzers, tuners, and software. The page is divided into five sections covering project discussion, design summary, an improved small loop, construction steps, and radiation pattern analysis. Aimed at hams interested in building their own magnetic loop antennas, the page offers practical guidance and insights into impedance matching for improved performance.

2 Wavelength ,2 Meter Bi-Square Beam , 5dbd gain. This antennas are very cheeap to build and their radiation pattern is similar to a figure 8 with maximum signal through the loop but they may be used as a near-omnidirectional antenna

This guide provides step-by-step instructions on how to install a delta loop antenna for hams. It covers the necessary materials, tools, and installation process in a clear and concise manner. Whether you're a beginner looking to set up your first antenna or an experienced ham radio operator wanting to try a new antenna design, this guide is a valuable resource to enhance your radio communication setup.

This page presents an online calculator tool for determining the dimensions of various HF wire antennas operating between 1.8-30 MHz. Users input their desired resonant frequency to obtain precise measurements for four popular antenna types: standard flat-top dipole, inverted Vee, quad loop, and equilateral delta loop. The calculator provides comprehensive measurements including leg lengths, minimum heights, horizontal spreads, and feedpoint distances. Accompanying the calculator are detailed technical explanations, construction notes, and installation guidelines for each antenna type, making it a practical resource for amateur radio operators building their own antennas.

WB8LZR details the construction and initial field results of a multi-band vertical wire antenna, designed to complement his existing horizontal loop for improved DX on 80 meters. The antenna utilizes a 67-foot vertical wire, configured as a quarter-wave radiator on 80m, and employs a 1:1 current balun for RF isolation on 80m, 30m, and 17m. For bands like 40m, 20m, and 10m, where the wire acts as a half-wave or full-wave radiator, an additional impedance transforming _unun_ is integrated to manage the significantly higher feedpoint impedance and voltage. The author notes the vertical's performance as a receiving antenna, observing reduced noise compared to his main horizontal loop, particularly on 80m, and even hearing some long-path signals the loop missed. Initial QRP contacts, including a **1-watt** QSO with a _VP2 station_ on 30m, demonstrate its transmit capability. While the radial system is currently rudimentary, the project outlines practical considerations for multi-band vertical deployment and impedance matching.

A dual band X-frame wire antenna made using 4 turns for response down to 3 MHz or so, and 2 turns (switched) for response up to around 18 MHz. The loop configurations are tuned using common eBay 365 pF tuning caps.

The 80-meter Skyloop antenna, a top-performing HF antenna, excels in weak signal work, low-noise operation, and omnidirectional coverage. Ideal for fixed stations, it delivers strong performance at low power, outperforming many alternatives, including 80m half-wave end-fed antennas. Requiring significant space for deployment, it’s well-suited for NVIS and groundwave use. Though not portable, it’s cost-effective and durable, with minor maintenance needs. Tuning may require adjustments for optimal resonance. It’s a standout for base stations, though a lighter portable version could enhance its versatility.

Notes on installing the miniVNA PRO software, making a calibration standard, a trap tuning loop.

A Magnetic Loop Controller project details the construction and operation of an automatic tuning system for magnetic loop antennas, which are resonant circuits using an oversized inductor and an adjustable capacitor. The system employs a stepper motor to precisely adjust the variable capacitor, maintaining optimal resonance across the HF bands. It integrates with various transceivers, including _Icom_, _Kenwood_, and _Yaesu_ models, by monitoring the VFO frequency and adjusting the loop's tuning accordingly. The project provides comprehensive building instructions, a PowerPoint-style presentation, and the full source code for the controller's firmware, enabling hams to replicate and customize the design. The controller's firmware offers diverse functionality, including automatic frequency tracking, manual tuning, and SWR monitoring, significantly enhancing the operational efficiency of magnetic loop antennas, particularly for QRP and portable operations. The design emphasizes accurate capacitor positioning, crucial for achieving low SWR and maximum radiated power. Comparisons with manual tuning methods highlight the benefits of real-time adjustment, especially when operating across different bands or making frequent QSYs. The project's detailed documentation and available source code facilitate experimentation and modification by advanced builders, allowing for tailored performance characteristics.

This antenna works on 17, 20, and 30 meters, with the best bandwidth on 20 meters. The bandwidth on 17 and 30 is quite small but usable. There is a 20 KHz bandwidth on 20 meters.

In this article the author feature the various types of beam antenna that can ben builw using wires, like moxon, spieder and hex beam, delta loops, bird yagi

A small magnetic loop antenna, often employed by hams facing antenna restrictions or high local RFI, offers a compact solution for HF operation. This resource details the construction of a foldable magnetic loop designed for the 40m through 17m bands, emphasizing its high-Q factor and _Faraday coupling_ for effective noise rejection and narrow-band filtering. The guide outlines material selection, advocating for copper over aluminum to maximize efficiency, and provides insights into the physics governing its operation, including impedance matching and resonance principles. Practical application of this antenna design is particularly beneficial for QRP enthusiasts and portable operators seeking a stealthy, high-performance antenna. The construction process includes specific details for a 1-meter diameter loop, a 140pF variable capacitor, and a _gamma match_ for impedance transformation. Performance comparisons suggest that while a full-size dipole might offer slightly better gain, the magnetic loop's ability to mitigate local noise often results in a superior signal-to-noise ratio, making it a viable option for challenging RF environments.

A comprehensive overview of a 10-band attic antenna system developed for contesting and DXing is presented, covering its evolution and performance. Initially intended in a restricted location, the system has been developed through numerous iterations, using various antenna types such as delta loops and Yagis. Automatic switching, dual-direction capability, and optimum tuning for certain band segments are among the most notable features. The project not only improves operating efficiency but also provides great learning opportunities in antenna design and installation in restricted places.

This project explores the construction and performance of an Alford Loop antenna as an alternative to a round loop. The Alford Loop, symmetrically fed at opposite corners, behaves like a small loop despite its larger size. Built using PVC pipes and secured with tire wraps, the antenna integrates an LZ1AQ active amplifier for optimal performance. With deep nulls in its horizontal radiation pattern and improved resonance characteristics, this design has significantly outperformed previous active antennas in reception quality.

This project is for those ham amateurs who do not have a commercial one . It's easy to build with a soldering iron, a plastic case and a little knowledge of arduino. The controller is made with budget components you can find easily in Internet. The main component is a cnc shield that fits over an Arduino Uno. Both made a compact, small and cheap controller.

Learn how to build a simple tuned loop antenna for the AM broadcast band to improve the performance of your radio receiver. Discover how to construct a loop antenna with readily available materials, such as balsa and basswood, without the need for specialized woodworking tools. Follow step-by-step instructions to create a portable loop antenna that offers good gain and directivity, ideal for pulling in weak stations. Enhance your Ultralight DX'ing experience and explore the world of FSL antennas through this practical DIY project.

Original HF magnetic loop antenna designed by the author to work in conjunction with QRP transceivers like the FT-817 in portable operations. In this configuration the loop can operate from 30 to 10 meters. Using a two spires radiator of the same diameter it also covers 40 meters.

Learn how to build a portable receiving antenna for the 160 meter band. This guide provides detailed instructions on constructing a loop antenna using a coaxial cable RG-316 with SMA connectors. The antenna weighs 1.7 kg and has dimensions of 2m in height and 1.892m in width. The wooden frame consists of four 0.945m long pieces and two 1m long pieces. Perfect for hams looking to enhance their 160m band reception during travel or portable operations.

This PDF document provides detailed information on small loop antennas for hams. It covers the design, construction, and usage of small loop antennas for amateur radio operators. The guide includes practical tips and recommendations for optimizing the performance of small loop antennas in various operating conditions. Whether you are a beginner or an experienced ham radio operator looking to improve your antenna setup, this guide has valuable insights to offer.

An homebrew HF Magnetic loop made with 2m length of 6mm diameter copper pipe formed into a near circle as the low loss inductor, a short length of coax as a capacitor,a short length of mains cable, again as a fixed tuned capacitor, a tunable 365pF air spaced capacitor, and a small Jackson C804 airspaced variable with a small 3-35pF trimmer in parallel

Discover the best low band receive antennas for hams with limited space. Learn about the K9AY loop antenna and Shared Apex Loop Array, two alternatives to the traditional Beverage antenna. Understand the concept of Relative Directivity Factor (RDF) and compare the performance of different receive antennas. See how the Shared Apex Loop, patented by Mark Bauman (KB7GF), offers an RDF between 8 and 10dB. Find out how to optimize antenna performance and enhance your receive capabilities on 160, 80, and 40 meters. Explore the world of low band receive antennas with insights from WB5NHL Ham Radio.

Setting up a portable wire delta loop antenna with an MFJ 33ft telescopic fiberglass pole

The Score Distributor facilitates real-time score forwarding for amateur radio contests, automatically transmitting data from various logging software to multiple online scoreboards. By configuring logging applications to send score data to the Distributor, operators ensure their current score is simultaneously represented on platforms like the _Contest Online ScoreBoard_ (COSB) and the Live Contest Score Server by R4WW. This system eliminates the need to choose a single scoreboard, providing broader visibility for participants. This utility enhances the competitive experience by allowing contesters to monitor their performance against other stations throughout an event. Observing real-time standings can provide significant motivation, particularly during periods of challenging propagation or when striving to maintain pace with club members or peers. The platform supports almost all major contest logging software, simplifying integration for a wide range of operators. Developed by WA7BNM, the Score Distributor was last revised on June 14, 2023. It aggregates score data, offering a unified point of submission that then disseminates the information, ensuring a **single point of entry** for broad scoreboard coverage and improving the dynamic feedback loop for participants.

Integrating a _Software Defined Radio_ (SDR) into an existing ham radio setup involves connecting it with a standard transceiver (TRX), power amplifier (PA), and antennas. The core component is a splitter box that facilitates the connection between the TRX and the SDR, allowing for simultaneous operation without modifying existing equipment. In receive mode, the splitter ties the antenna inputs of both the TRX and a direct conversion receiver (DC RX) together. During transmission, the DC RX input is grounded via a fast telecom relay controlled by the transceiver's -SEND signal, incorporating a 10ms delay for safety. The splitter box includes a 3.7 dB input attenuator for impedance matching and acts as a protective fuse for the DC RX input. Ground loops are mitigated using common mode balun transformers, while the DC RX input is insulated with a broadband transformer. An audio switch box complements the setup, enabling users to listen to either the main transceiver, the SDR output, or both simultaneously. This configuration ensures noise immunity and safety, with the splitter housed in a screened box made from PCB material. On-air tests, such as the CQ WW 160m CW DX Contest, demonstrate the system's effectiveness, showcasing the SDR's ability to handle crowded band conditions with superior selectivity and dynamic range. The SDR's narrow bandwidth filters and waterfall display provide significant advantages, allowing operators to detect weak signals amidst strong interference. The integration of SDR with conventional radios offers enhanced operational flexibility and performance in challenging environments.

This article details a ham radio operator’s experience setting up HF antennas in an antenna-restricted community. Initially using an AEA Isoloop magnetic loop for QRP PSK, the author later built an attic antenna system, including dipoles for multiple HF bands and a slinky dipole for 40 meters. The setup allowed for operation on six bands with acceptable VSWR. Despite space constraints and some compromises, performance was effective. The article highlights practical strategies, emphasizing experimentation and antenna modeling for optimizing performance in limited-space environments. A valuable guide for ham radio operators facing similar restrictions.

This page provides a detailed guide on how to build your own radioless Allstar node for ham radio operators. It includes information on power supply, components needed, wiring instructions, and tips to avoid common issues like ground loop hums. The author shares personal experiences and recommendations for specific components like microphones, audio amps, and sound fobs. Whether you're a beginner or experienced ham radio operator, this DIY project can help you set up a cost-effective and functional Allstar node for communication purposes.

This article provides an in-depth review of the Ciro Mazzoni Baby Loop Ham Radio Antenna. The author, a ham radio operator, compares this magnetic loop antenna with his usual End Fed Half Wave antenna, discussing the performance and installation considerations. The post explains the concept of loop antennas, resonating frequencies, and the benefits of using a small loop antenna with a capacitor for optimal operation. If you are looking for information on magnetic loop antennas and their effectiveness in restricted spaces, this review offers valuable insights and practical experiences for ham radio operators.

This page allows hams to design a vertical-plane delta-loop antenna for a single amateur HF band in different configurations. By choosing different feed-point positions, operators can observe variations in polarization properties, radiation patterns, and feed-point impedances. Users can generate radiation pattern plots, VSWR charts, antenna current diagrams, and Smith charts for their antennas over various ground types. Through adjusting the antenna's physical dimensions and refreshing the plots, hams can gain insights into the antenna's performance in the field. The page also discusses how elevation radiation patterns may change based on the antenna configuration and feed-point position.

Unveil the secrets of efficient Magnetic Loop Antenna control systems, eliminating the hassle of frequent retuning. With real-time tracking and compatibility with various transceivers, including popular models from Elecraft, ICOM, Kenwood, and Yaesu, this controller ensures seamless frequency adjustment. Explore its high-resolution stepper motor and versatile communication capabilities, revolutionizing amateur radio operation.

Learn how to design a Hentenna antenna, a portable asymmetrical double-loop antenna ideal for amateur HF or VHF bands. This page provides details on constructing and optimizing the antenna for maximum performance in DX communications. Discover how altering the antenna's vertical feed section can adjust the VSWR resonant frequency and how changing the support pole's position can alter the beam direction. Originally developed by Japanese 6-meter operators, the 'Hentenna' offers a unique design that allows for horizontal polarization when vertically oriented. Explore radiation patterns, VSWR charts, and antenna currents diagrams to optimize your antenna's performance for long-distance contacts.

The tri-band trapped delta loop antenna design operates on 80 meters (3.5–4 MHz), 40 meters (7–7.3 MHz), and 30 meters (10.1–10.15 MHz) using a single triangular wire loop. This configuration eliminates the need for an external antenna tuner or band-switching relays. The antenna's physical perimeter, approximately 270 feet, establishes 80M as the fundamental band, with specific trap placements enabling resonance on 40M and 30M. Trap design and placement are critical, with 30M traps positioned inboard of 40M traps within the horizontal element. Each slant leg measures approximately 80 feet. The resource references foundational information from the _ARRL Antenna Handbook_ and _ON4UN’s Low Band DXing_ regarding full-wave loop behavior and feedpoint impedances. The project aims to provide multi-band HF operation from a single, fixed antenna structure.

A vertical delta loop is a practical antenna for low bands, popular for its simple design requiring just one support. Its shape, an equilateral triangle in free space, yields optimal gain and radiation resistance. Deviating from this shape lowers performance. The delta loop can be polarized either horizontally or vertically based on the feed point location. In vertical polarization, it acts as two quarter-wave verticals with the baseline feeding one side. This design minimizes radiation from the baseline while maintaining effective operation.

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.

Delta loop antennas, particularly the 30 meter variant, offer unique advantages in terms of vertical polarization and omni-directional coverage. The construction process detailed by VE3VN highlights common mechanical and electrical challenges faced by amateur radio operators. Key design considerations include minimizing interaction with existing contest band antennas, achieving low elevation angles for DX chasing, and ensuring the antenna remains off the ground for agricultural clearance. The article provides specific measurements, such as the loop's height and feed point impedance, which are critical for optimizing performance. The use of NEC modeling software illustrates the importance of accurate resonance calculations, revealing how proximity to the tower affects both pattern and impedance. This practical account serves as a resource for hams looking to build effective antennas while navigating typical construction hurdles.

This resource details the construction and performance of a compact broadband magnetic loop antenna designed for portable receiving applications with devices like the _ATS MiniRadio_. The antenna utilizes approximately 3 meters of 0.5–1 mm copper wire wound in two turns on a rhomboidal wooden frame, measuring 50 cm by 70 cm. It connects via a modified 9:1 unun, where the primary center tap is isolated from ground to improve common-mode noise rejection. The design provides untuned operation across a frequency range from the longwave band up to approximately 25 MHz. Performance characteristics include observable directivity for noise suppression and the ability to connect directly to a radio or via a 50 coaxial cable for remote operation. The article specifies the unun's 3:1 turns ratio and its SMA output for connectivity. The methodology focuses on practical construction and observed reception quality.

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.