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Query: beam antenna
Links: 221 | Categories: 4
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An easy to build moxon antenna for portable use. A Moxon Rectangle is a two element beam, where both elements are folded towards eachother. -
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Online javascript antenna calculator designed to give the critical information of a particular beam antenna, in this case a seven element Yagi, for the frequency chosen. -
A suitable high gain 70cms antenna for SOTA operation was sought that did not have the drawbacks of a long Yagi antenna, principally a narrow beamwidth and bandwidth. -
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 -
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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. -
7 dB for 7 Bucks, a 2 meter beam antenna for the cost of a fast food meal! -
A 7 elements yagi beam monoband antenna for 14 Mhz by VE3GK -
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 -
How to homebrew an hex beam antenna for 20 17 15 12 10 meters band by VA7ST -
Article by Ed Bathgate, N3SDO as published in CQ VHF Magazine July, 1988 -
BEAM_DX is a free windows software for radioamateurs or radio listeners usage. It allows to point a directionnal antenna towards an azimuth, a locator, an international prefix or any other geographical position on earth predefined by its latitude and its longitude -
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. -
Hexagonal wire beams for all hf bands, technical resource, EZNEC files, tools for antenna modeling and documentation. You can also order parts to build your own antenna. -
Located in France, DXBeam designs and manufactures a range of monoband, dual band and triband antennas, rotary dipoles, Moxons and Yagis -
A two elements beam antenna tunable from 6 to 20 meters, based on the Maria Maluca antenna project by DB9EX, in german -
The Upside-Down Umbrella Antenna by Don Keith N4KC -
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Here is an antenna for the nineties. It's strong, computer designed, and has lots of gain. It is a full size, four element beam on 10, and three elements on 15 meters -
A simple beam antenna offering good performances on 3 bands by 9m2mso -
The "Tiny 2" is a great little 2 meter beam. It has some really interesting properties and it is a fantastic first time antenna project for the beginner. -
This design was adapted from an article in the ARRL Handbook and built with simplicity and duplicity in mind. This antenna is a vast improvement over a standard dipole with a forward gain of around 8db with a front to back ratio of 10db. -
G3TXQ pages focuses on understanding the HexBeam antennas. Basics, dimensions, multi band issues, antenna modeling. -
VA3EXT 5 element beam antenna for 6 meters band -
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Solves antenna matching problem with two phased antennas. Stacked rotary beams are popular. However, connecting two 50 Ohm antennas together presents some problems. -
A project for a homemade multiband Hexbeam antenna for 10, 12, 15, 17 and 20 meters -
In these slides, differences between spiderbeam antenna and hexbeam antennas are explained comparing performances and measurements. -
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An antenna originally planned in the sixties, a two element beam antenna tunable on several band, in french -
A moxon antenna project for 70 cm band, test and results of this popular antenna model applies to UHF bands. -
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. -
Demonstrates the design and construction of a compact, portable multi-band mini-delta loop antenna, specifically optimized for /P (portable) operations from remote locations like Scottish islands. The resource covers the theoretical underpinnings of half-wave loops, contrasting closed and open configurations, and then details the application of a folded dipole principle to achieve a 50-ohm match for direct coax feed. It presents empirical formulas for calculating element lengths, considering the velocity factor of common wire types, and provides a detailed example for a 20m (14.175 MHz) version. The article includes a comprehensive table of dimensions and allowances for a five-band (20m, 17m, 15m, 12m, 10m) mini-delta beam, along with construction hints for the central support and balun. It specifies a 1:1 trifilar balun wound on a ferrite rod and describes the antenna adjustment process using an _MFJ-259B Antenna Analyser_. Initial test results indicate an SWR of 1:1 at resonance and a bandwidth of approximately 240 kHz on 20m, even at a low height of five feet above ground. The distinctive utility lies in its focus on a practical, easily deployable beam antenna for portable DXing, offering a viable alternative to more complex or larger arrays. -
Electronically controlled HF antennas. General coverage. Top features on all ham bands. Very advanced materials and state of the art technology. -
The Vee Beam antenna project presents a versatile solution for hams, enabling operation across all eight High Frequency bands (80m to 10m) with significant gain on 20m to 10m. This easy-to-construct antenna utilizes two long wires at an angle, enhancing directional performance and minimizing ground losses. With a low visual profile, it is discreet and effective for various applications. The design allows for optimal leg lengths and included angles, ensuring robust performance while maintaining simplicity in construction and operation. The V Beam antenna is an aerial that you can use on all eight High Frequency amateur bands (80, 40, 30, 20, 17, 15, 12 and 10m) with an antenna tuner, and which gives significant gain on the five bands from 20 to 10 meters band. -
A 4 yagi beam VHF antenna made with PVC easy to carry in a backpack for portable operations -
Description of the 80m antenna used at CN2WW in the ARRL-DX CW 2007 -
50 MHz meteor scatter offers a unique opportunity for amateur radio operators to make long-distance QSOs, even when the band appears dead. Meteor scatter involves reflecting radio waves off the ionized trails left by meteors burning up in the upper atmosphere, typically around 105 km high. These trails can facilitate contacts over distances up to approximately 2,300 km. The technique is particularly effective during meteor showers, which increase the number of meteors and thus the chances of successful QSOs. However, random meteors can also be used to achieve contacts, especially on the 50 MHz band, where the longer reflection time compared to 144 MHz makes it easier to work meteor scatter. Operators should be prepared to make QSOs in short bursts, often lasting only a few seconds. The IARU Region 1 meteor scatter procedure recommends using 2.5-minute periods for telegraphy and 1-minute periods for SSB, though shorter periods can be arranged. For 50 MHz SSB, 15-second timing is often used to maximize the chances of completing a contact. The procedure involves specific timing for transmissions based on direction and requires both operators to confirm receipt of callsigns and reports to complete a QSO. Understanding the geometry of meteor scatter, including the optimal radiation angles and the concept of 'hot spots,' is crucial. These hot spots are areas where reflections are most likely to occur, influenced by the Earth's rotation and the path of the meteors. Proper antenna setup, including elevation control and beam direction, can significantly enhance the chances of successful meteor scatter QSOs. -
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. -
Notes on moxon antennas for VHF and HF bands. Main characteristics, gain and f/b ratio by DK7ZB -
The HB9CV is a well known two element antenna of a directional beam type with a forward gain of 4 to 5 dBd. This one is for two metres but it can be scaled, from the dimensions in the diagram, for other bands I have also made them for four and six metres -
In the long history of beam aerials there has persistently existed the claim that certain types of aerials perform better than yagis.