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For radio amateurs considering homebrew antenna projects, this resource details several designs from WE6W, an experienced operator. It covers the construction and characteristics of a _160 Meter QRP Loop Antenna_ optimized for high voltage, along with standard and folded variations of the double bazooka antenna. The site also presents a unique Field Day antenna design and instructions for building a Sterba Curtain, a directional array known for its gain. Each design includes practical insights from the author's building experience. The author provides comparative data, such as the performance of a standard bazooka against a traditional dipole, offering real-world context for antenna selection. The Sterba Curtain section includes notes on its beamwidth and gain, crucial parameters for directional operation. These designs are suitable for hams looking to experiment with cost-effective, high-performance antennas for various bands and operating scenarios, from QRP on 160m to directional DXing with a Sterba Curtain, which can offer significant forward gain, often exceeding **10 dB**.

4 Element Cubical Quad, Yagis, LZA Circular Quad, Shrunken Quad , quarter wave, J-Pole, beam mounting , changing polarity

The HB9ABX RoomCap antenna document details the construction and performance characteristics of a compact HF antenna design. It presents a series of comparative field tests conducted between July and September 2005, evaluating the HB9ABX antenna against established designs like the Microvert MV-500, Cushcraft R5/R7000 verticals, and a 5-element DJ2UT Yagi beam. Specific test scenarios include mobile installations, rooftop deployments, and comparisons on 20m, 40m, 80m, and 160m bands, with signal reports from various European and DX stations. The resource emphasizes the antenna's small physical footprint and its claimed efficiency across multiple HF bands. Test results consistently show the HB9ABX antenna performing comparably to, and often outperforming, larger reference antennas in terms of received signal strength, with reported differences of 1 to 2 S-points (6-12 dB) in many contacts. Notably, a 20m DX test on July 26, 2005, indicated the 1.3m HB9ABX radiator yielded 2-3 S-points stronger signals than an R7000 vertical for US DX stations. An August 12, 2005, test on 40m highlighted the HB9ABX's superior signal-to-noise ratio in urban QRM, demonstrating 10-18 dB better performance than an R7000. The document includes specific callsigns, signal reports, and QTHs for each comparison, providing empirical data for the antenna's performance claims.

Details the construction and optimization of antenna systems for amateur radio satellite operations, focusing on practical, homebrew solutions for VHF/UHF bands. It covers building _groundplane antennas_ from salvaged materials, recycling old beam antennas into new configurations like a 2-meter crossed yagi, and constructing a 10-meter horizontal delta loop. The resource also explains antenna matching techniques, including folded dipole driven elements and quarter-wave transformers, along with the importance of accurate SWR measurements and minimizing coax loss. Demonstrates how to achieve a **1:1 SWR** by carefully trimming elements and adjusting radial angles on groundplane antennas. It provides insights into selecting appropriate coax and connectors, highlighting the benefits of Belden 9913 for low loss and the proper installation of _N-connectors_. The article also addresses RFI mitigation from computer birdies and presents a design for a silent triac antenna control circuit, offering practical solutions for common satellite station challenges.

80m to 23cm beam antennas, oscar antennas, and antenna rotors

Here you will find information about wire antennas as well as directional beams.

The page provides detailed information about the construction of a full-size 160M 3 element beam antenna and an 80M 5 element beam antenna on a 330ft tower. It includes specifics about the tower height, types of antennas, elements, gain, take off angles, front-to-back ratio, operating frequencies, weight, and dimensions of the beams. The content is aimed at amateur radio operators interested in building high-performance antennas for the 160M and 80M bands. This Antenna is now been destroyed and is no more operational.

HF Vertical and Beam Antennas, antennas accessories by Butternut. Bencher is out ouf ham radio business. Recently company products has been sold to Vibroplex and DX Engenieering.

The KD6WD Moxon Antenna Project details the construction of 50-ohm two-element wire beam antennas, specifically Moxon rectangles, for the 10, 15, 17, and 20-meter bands. It utilizes AC6LA's software for critical measurement calculations (A-E) based on center frequency and wire size. Construction involves 16-gauge silver-coated copper wire, 16-foot telescoping fiberglass crappie fishing poles as spreaders in an "X" configuration, and various hub designs including aluminum tubing or PVC joints. A 1:1 current balun is used at the feedpoint, with wire nuts for connections, often achieving a 1:1 SWR across the design band. The project highlights practical applications, such as running a kilowatt into the antennas for greyline DX contacts, consistently yielding excellent signal reports. Comparisons to quad loops show 4 to 5 S-unit improvements in both receive and transmit. The Moxon design, according to L.B. Cebik's analysis, offers superior forward gain and front-to-back ratio among wire beams. The author notes a "DX-Vane" effect where a freely suspended Moxon automatically points to the strongest DX signal. Attempts at dual-band operation (17/20 meters) with a single feed were unsuccessful, reinforcing the Moxon's monoband nature, with EZNEC plots provided for a 17-meter Moxon at 30 feet.

Selecting an appropriate antenna system for shortwave broadcasting involves evaluating various types based on performance, cost, and operational parameters. This resource details the critical specifications for broadcast antennas, including average and peak power ratings, directivity, takeoff angle (TOA), horizontal beamwidth, and gain, emphasizing that a 100-kW transmitter requires an antenna rated for 150 kW average and 400 kW peak. It clarifies that low TOA signals travel thousands of kilometers, while high TOA is for local coverage, and nearly all modern shortwave broadcast antennas are horizontally polarized. The article explores specific antenna types, such as Log-Periodic Antennas (LPAs), which offer wide frequency ranges (e.g., 2-30 MHz) and directional patterns with 11 dBi gain, costing from $20K to over $100K for multi-curtain versions. Dipole arrays, also known as curtain antennas, are prevalent in international broadcasting, featuring steerable beams (±15° and ±30°) and mode-switching capabilities to alter TOA, with high/low pairs costing over $1 million. Fan dipoles are noted for omnidirectional patterns, smaller size, and lower cost for low-power applications, while rhombics, though simple, require resistive termination and incur several dB of I2R losses. Balun considerations are crucial, as most communications baluns are not rated for the higher average and peak powers of AM broadcast transmitters. Modern shortwave antennas utilize durable materials like Alumoweld wire rope for radiators and support elements, avoiding copper, fiberglass, or materials prone to stretching or deterioration. Feeder systems for high-power stations often require tapered-line baluns to convert 50-ohm unbalanced power to 300-ohm balanced for connection to the antenna.

Examines the practical considerations and technical challenges of deploying mobile antennas for 10-meter operation, particularly for operators on the move. It addresses the inherently _lossy_ nature of shortened, loaded vertical antennas typically used in mobile configurations, encouraging hams to view these limitations as engineering challenges. The resource provides actionable advice on safeguarding vehicle electronics, selecting appropriate cabling like _RG-213_, and properly grounding antenna mounts to the vehicle chassis. Specific mounting strategies are detailed, including roof, trunk lip, and side-mounting for trucks and vans, along with their respective advantages and drawbacks. It emphasizes the importance of a robust ground plane and suggests methods for improving grounding beyond simple set screws. The article also touches on antenna choices, mentioning "bugcatchers" and "Hamstick types" as viable options for 10 meters. Furthermore, the guide transitions to stationary mobile operation, where antenna options expand significantly. It outlines how to deploy portable dipoles or 2-element beams from a parked vehicle, offering practical tips for assembly, storage, and mast guying using simple materials like a concrete block. It notes that a 5/8 wavelength height, approximately **20 feet** on 10 meters, often yields good short-skip and DX performance, even with a take-off angle above **20 degrees**.

Using delta match with HF antennas design

Simple gain antennas for the beginner, a 2 element HF yagi antenna

8 and 4 elemets yagi beam antenna by N6CA

Two element X-Beam is a high-performance broad-band antenna that is ideal for Ham radio operators with limited space. X-Beams are inexpensive and easy to build. The performance of the simple X-beam is amazingly similar to larger, more conventional antennas by 4S7NR

Designing a compact directional antenna for the 70cm band involves balancing gain, front-to-back ratio, and physical size. This resource details the construction of a 2-element Moxon rectangle antenna for 432 MHz, outlining the specific dimensions for the driven element and reflector, and discussing the advantages of its folded dipole configuration. The article provides insights into the historical context of 70cm operations and the author's personal experiences with early 432 MHz transceivers and antenna setups, such as a Jaybeam 48-element TV antenna. It also touches upon the practical aspects of building and deploying such an antenna for local and weak-signal work. The Moxon antenna design is compared to a 3-element Yagi, noting its superior front-to-back ratio and broader bandwidth for a given boom length, making it suitable for portable operations or restricted spaces. The construction uses readily available materials like copper wire and PVC tubing, emphasizing simplicity and ease of replication. Performance characteristics, including a reported gain of approximately 5.5 dBi and a front-to-back ratio of 20 dB, are discussed in the context of its compact footprint. The resource includes a visual representation of the antenna's dimensions and construction, aiding in practical implementation.

An antenna does not have to be resonant to work, as the primary reason for resonance is to eliminate the need for an impedance-matching device. A non-resonant wire dipole fed with open-wire line and an antenna tuner can function as an effective multiband antenna. Two wires are essential for powering an antenna, ideally with a balanced configuration like a dipole fed by parallel-wire line, though coaxial cable can be used with a 1:1 balun to mitigate RF feedback on the shield. Antenna gain is achieved by shaping and aiming RF energy, concentrating it in a particular direction, as seen in beam antennas or shaped radiation patterns of wire antennas. The function of an antenna tuner is to match the transceiver's 50 Ohm output to the antenna system's impedance, which can vary widely. Wire antennas do not always require center feeding; end-fed long wires or off-center-fed dipoles (Windom antennas) can be used, often requiring a counterpoise or radial system. Dipole antennas do not need to be perfectly horizontal; their legs can be bent, inclined, or even vertical, affecting feed point impedance. Vertical antennas shorter than a half wavelength necessitate a ground system, typically comprising radial wires, with more radials generally leading to greater efficiency. A 1:1 SWR indicates an impedance match but does not guarantee a good antenna, as an inefficient antenna with a poor ground system can still show a perfect SWR while wasting RF as heat. Always using the best feed line affordable is crucial for minimizing loss and maximizing RF signal delivery to and from the antenna.

Discuss here about hex-beam antennas

Operating on the 12-meter and 17-meter WARC bands often benefits from directional antennas that offer gain and front-to-back ratio in a compact footprint. This resource details the construction of a dual-band wire beam, specifically a _Moxon Rectangle_ design, for these two bands. It outlines the use of fiberglass tubing for spreaders, _Flexweave_ wire for the elements, and an aluminum hub with die-cast flanges to create a robust structure. The design allows for a single 50-ohm feed point, simplifying station setup and minimizing feedline loss. The project provides specific dimensions and material choices, enabling a homebrewer to replicate the antenna. While inspired by L.B. Cebik's (W4RNL) theoretical work, this implementation focuses on practical construction techniques for a physical build. The resulting antenna offers directional characteristics suitable for DXing and contesting on 12m and 17m, providing an alternative to full-sized Yagis or compromise verticals, particularly for those with limited space.

A javascipt online calculator for 2 and 3 element beam antennas. Just input frequency and will diplay element dimensions and spacing. Measurements in Feet and Meters by G4VWL

An experimental antenna, similar to the _TAK spiral antenna_, was evaluated for SWR response over the 7.0 to 7.3 MHz frequency range. The analysis presents specific results: beam length significantly affects SWR, with increased distance between spirals raising the resonant frequency; the combined length of antenna and hookup wire lowers the resonant frequency as it increases; and spiral diameter impacts bandwidth, with larger diameters yielding greater bandwidth. The design addresses the fixed beam length limitation of the commercial TAK antenna by introducing an adjustable version constructed primarily from PVC electrical conduit and water pipe, using 14-gauge aluminum wire. The resource includes a detailed mechanical design, construction steps, and a parts list. It also features a spiral antenna spreadsheet model for calculating design parameters like start point, pitch, safe edge, spoke length, and arm length, which aids in determining wire length and kerf cutting tables. Model verification involved constructing an antenna to specific parameters, with SWR tests conducted using an _MFJ Model 269_ antenna analyzer at 13 feet above ground with 60 feet of RG8 mini coax. Measurements showed that adjusting beam length from 27 to 37 inches shifted the resonant frequency by approximately 0.18 MHz. Further data compares 32-inch versus 48-inch diameter spirals, demonstrating increased bandwidth for the larger diameter. The model accurately predicted revolutions for given antenna lengths, pitch, and starting distances. The final design achieved a resonant frequency of 7.17 MHz, favoring the voice portion of the 40-meter band after adjustments.

The document details the optimization and construction of the _Maria Maluca_ antenna, a compact 6-band (20m-6m) directional beam. It presents a comparative analysis of shortwave antenna principles, highlighting the efficiency gains achieved by using an open feeder line and tuner as a resonant unit, contrasting this with the losses associated with traps or capacitive loads in multiband antennas. The resource specifically revisits an older South American 2-element design for 10, 15, and 20 meters, applying modern NEC-based software to develop a six-band version. Performance data is meticulously tabulated, showing impedance, free space gain, gain at 12m height, elevation angle, and front-to-back (F/B) ratio for each band from 20m through 6m. For instance, on 15m, the antenna achieves 5.1 dBd free space gain and 13.72 dB F/B ratio. The construction section provides practical guidance on element assembly using aluminum pipes and hose clamps, detailing the use of a heavy-duty glass fiber reinforced polyamide rod for electrical separation and bending strength. It also specifies the use of 450-ohm _Wireman_ line CQ 552 for the transmission line. The document includes diagrams for rod fixing, an air-wound balun, and a vertical elevation diagram for the 15m band, illustrating its DX qualification. It also discusses the antenna's suitability for portable and expedition operations, noting its compact transport dimensions (max 1.50m length, 12 lb weight) and quick assembly time (under 15 minutes). The author, Dipl.Ing. Helmut Oeller, DC6NY, is identified as a source for material kits.

A 144 MHz six element yagi beam antenna plan

For radio amateurs seeking compact, directional antenna solutions, the Moxon Rectangle offers an attractive alternative to traditional two-element Yagis. This resource compiles several articles by L. B. Cebik, W4RNL, exploring the **Moxon Rectangle** design, which provides gain comparable to a full-size two-element array but with a significantly improved **front-to-back ratio** and a direct 50-Ohm feedpoint match. The collection covers both wire arrays, particularly for lower HF bands, and rotatable aluminum beam constructions, addressing various aspects of this popular antenna configuration. The articles delve into specific band applications, including designs for 10 meters, 40 meters, and 2 meters, alongside discussions on multi-banding techniques and pattern characteristics. Comparisons are drawn between the Moxon and other antenna types, such as VK2ABQ Squares, highlighting the Moxon's advantages in terms of size and performance. Practical construction notes are provided for both wire and aluminum versions, offering insights into building these antennas for different operating environments.

Animated quad and yagi comparison. You can see antennas' characteristics behavior in a vertical plane with changing of the height.

The Charles Gizmotchy high performance horizontal and vertical beam antennas. Two, Six, Ten and eleven meters antennas

A compact Beam Antenna That Can Be Built At Home. Made with lightweight wooden "X" frame with two folded and linear loaded wire elements. The two elements are approximately a half-wave each.

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

Presents a comprehensive guide for constructing a broadband Hex Beam antenna, a popular directional array for HF operation. This design offers a compact footprint and excellent gain characteristics, making it suitable for limited space installations while providing significant performance advantages over omnidirectional antennas. The resource details the specific dimensions for a five-band Hex Beam covering 20, 17, 15, 12, 10, and 6 meters, emphasizing the critical element spacing and wire lengths required for proper resonance and pattern. It outlines the construction of the center post, spreaders, and wire elements, along with the feed point assembly, ensuring proper impedance matching. The project aims for a forward gain of approximately **5.5 dBi** on most bands, with a front-to-back ratio often exceeding _20 dB_. Building this antenna requires careful measurement and assembly, but the resulting performance provides a substantial upgrade for DXing and contesting.

optimum short-wave antennas, developed by hams for hams

Located in France, DXBeam designs and manufactures a range of monoband, dual band and triband antennas, rotary dipoles, Moxons and Yagis

Illustrates the construction of a compact _Moxon_ beam antenna specifically tailored for the 40-meter band (7 MHz). The resource details a homebrew project by W7XA, emphasizing its design for limited space while maintaining good bandwidth and directivity characteristics. It highlights the practical application of the _Moxon_ rectangle model to achieve performance on a lower HF band. The primary content is a downloadable PDF document titled "40-Meter-Mini-MOXON-Beam-Antenna.pdf," which provides comprehensive illustrations and technical specifications for replicating the antenna. This includes dimensions, materials, and assembly instructions, making it a practical guide for radio amateurs interested in directional antennas for HF. The project demonstrates how a relatively small footprint can yield a directional antenna suitable for DXing or contesting on 40 meters, a band typically requiring much larger arrays for similar gain and front-to-back ratios. The documentation supports hands-on construction.

G3TXQ pages focuses on understanding the HexBeam antennas. Basics, dimensions, multi band issues, antenna modeling.

Solves antenna matching problem with two phased antennas. Stacked rotary beams are popular. However, connecting two 50 Ohm antennas together presents some problems.

In these slides, differences between spiderbeam antenna and hexbeam antennas are explained comparing performances and measurements.

The **70cm Moxon Beam** project outlines the construction and testing of a compact, directional antenna for the 432 MHz band. G3XBM recounts his early 1980s experience with a 4W FM321 transceiver and a Jaybeam 48-element TV antenna, which provided a baseline for his later UHF antenna experiments. This project focuses on a simpler, yet effective, design for local and regional contacts, emphasizing ease of construction and practical field results over complex theory. The article details the specific dimensions and materials used for the Moxon rectangle, including 6mm diameter aluminum tubing for the elements and a PVC boom. G3XBM notes that the antenna was built for portable use, making it lightweight and easily deployable for field operations. The feedpoint impedance was measured at 50 ohms, ensuring a direct match without the need for an external tuner, which simplifies setup. Performance tests included comparisons against a commercial 5-element Yagi, revealing that the Moxon provided comparable forward gain and an excellent front-to-back ratio, crucial for reducing local QRM. The author's observations confirm the Moxon's reputation as a robust performer for its size, suitable for both fixed and portable 70cm operations.

NEC4WIN is a 32 bits commercial antenna simulation software based on MININEC3 developed by the Naval Ocean Systems Center in the 70s and 80s. It runs under Windows and can be used to simulate, analyze and optimize wire antennas, beams, verticals, etc. NEC4WIN has limitations. They are the same as Mininec3 on which the engine is based.

Electronically controlled HF antennas. General coverage. Top features on all ham bands. Very advanced materials and state of the art technology.

Nowdays lots of people are putting up antennas to either beam in different directions at the same time or just to stack them and get a lower angle of radiation. Use this stackmatch to match you array.

The Moxon Beam, introduced by L. Moxon (G6XN), is a compact 2-element Yagi featuring a radiator and reflector with reduced dimensions, approximately 75% the size of a full-size beam. This design utilizes bent element ends for capacitive loading, which is superior to inductive loading with coils, resulting in greater bandwidth and lower losses. DK7ZB details that while the gain is slightly lower (0.5-0.7 dB) than a full-size beam, the _Moxon_ offers an exceptional front-to-back (F/B) ratio of 30 dB or more on its design frequency, surpassing other 2-element beams. The article provides specific dimensions for building wire _Moxon_ antennas for bands from 30m down to 10m, and also mentions a 2-m-Moxon. Construction guidance includes using fishing rods for lightweight spreaders and an aluminum tubing spider for support. The resource highlights the utility of _Moxgen_ by AC6LA, a freeware program that simplifies Moxon beam design and generates EZNEC output files for further analysis and tapering modifications. DK7ZB emphasizes that the design frequency should be set at approximately one-third from the band's beginning to optimize SWR performance, as SWR tends to rise more significantly below the design frequency. The bandwidth for SWR < 1.5 is noted as sufficient for ranges like 28.0-28.7 MHz and 21.0-21.45 MHz when constructed with aluminum tubes, though wire beams exhibit a narrower bandwidth.

how to make a gamma match for a antenna. The Gamma match is the most used matching device used for yagi beams.

Building a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

Dedicated to State-of-the-Art lightweight portable radio. Sotabeams produces and sells amateur radio products dedicated to ham radio portable operations. Antennas, supports and masts, filters, wires and more accessories for amateur radio.

A ATU for beam and vertical antennas by PA0FRI

A fractional bandwidth of up to 30:1 characterizes spiral antennas, making them highly effective across a very wide frequency range, often from 1 GHz to 30 GHz. The resource details two primary types: the **Log-Periodic Spiral Antenna** and the **Archimedean Spiral Antenna**, defining each with specific polar functions and illustrating their planar configurations. It explains that spiral antennas are typically circularly polarized, with a Half-Power Beamwidth (HPBW) of approximately 70-90 degrees, and a peak radiation direction perpendicular to the spiral plane. The content elaborates on critical design parameters affecting radiation, including the total length (outer radius) for lowest frequency, the flare rate ('a' constant) for optimal radiation versus capacitive behavior, the feed structure (often an infinite balun) for high-frequency operation, and the number of turns (typically 1.5 to 3 turns). It also discusses the theoretical impedance of 188 Ohms for Log-Periodic spirals, derived from Babinet's Principle, noting actual impedances are often 100-150 Ohms. The article presents a simple construction method for an Archimedean spiral, demonstrating VSWR and efficiency measurements. Measurements from a constructed spiral antenna show a VSWR that is fairly constant across the band, albeit with a mismatch loss of about 3 dB. The antenna efficiency remains around -5 dB (31.6%) across its operating range, indicating a decent wideband radiator despite opportunities for optimization.

The Gizmotchy high performance horizontal and vertical beam antenna for 2/6/10/11 meter bands

Antenna dealer, antenna masts, towers, mounts, antenna rotators, steppir and optibeam inrad dealer

Ground Plane - 1/4 wave vertical, J-Pole, 3 Element Yagi Beam and simple antenna supports

Fabricates baseplate components, and provides hardware kits for DIY hex beam, spiderbeam and moxon antennas.

The antenna described here is a direct-connect dual-rectangle beam for use on 70 cm between 440 and 450 MHz