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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.

N5IW ideas to build your own antenna in a restricted lot, or a stealth antenna. Includes PPT files of HF and VHF stealth antennas.

409 Shop is an Ham Radio and electronics online shop based on Hong Kong deliver worldwide. Ham Radio transceivers, batteries, swr meters, antennas and other ham radio accessories. Currently the shop seems to be out of business

5 Band 1/4 wave Telescopic Antenna. The 20m to 10m, antenna is simple and cheap to make, and has a performance that matches commercial antennas but at cost considerably lower. The design was purposely based on a telescoping fibre glass fishing rod as this allows it to be easily stowed away in the car.

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 potpourri of 160-Meter vertical antennas and modeling issues, inverted-L, 3-element parasitic array, 1/4-wavelength monopole

CB Radios And Antennas, Marine Radios, Scanners, Radar Detectors. Online store and repair service

Match & display imped of antennas, can graphically visualize and compare two sets of measured impedances simultaneously.

This article describe a small single wire antenna running on the side of the building allow operations on 80 meters band

Antenna Warehouse provides a range of certified quality wire products for amateur radio and general communication applications. Their inventory includes Francis antennas, known for their robust construction, alongside the versatile Select-A-Tenna series. The company also stocks Solarcon 10/11 meter base antennas, catering to specific band requirements for 27-28 MHz operations, and various Wilson antenna models. Beyond product sales, Antenna Warehouse offers services such as antenna tower installation, repair, and removal. These services support the complete lifecycle of antenna systems, from initial setup to maintenance and decommissioning. The product selection emphasizes components for both fixed station and mobile installations.

This technical note explores the application of **Moxon rectangle** antennas for WARC bands, specifically 17 and 12 meters, as compact directional alternatives to standard Yagis. It details three design approaches: a dual-band Moxon using open-sleeve coupling, a Moxon-Yagi combination, and a simplified 1.5 Moxon rectangle. The document provides specific dimensions in feet for aluminum tubing elements (0.75" and 0.5" diameter) for each configuration, along with projected free-space gain, front-to-back ratio, and feedpoint impedance (R+/-jX Ohms) across the respective band segments. Performance tables illustrate gain (dBi), front-to-back ratio (dB), and 50-Ohm VSWR for each design. The dual-band Moxon, despite its compact 7-foot boom, is not recommended due to extreme sensitivity to construction variations, leading to rapidly changing performance characteristics. The Moxon-Yagi combination, featuring a 17-meter Moxon and a 12-meter director-driver Yagi, is presented as a more practical and adjustable solution, offering stable performance with a 10-foot boom. NEC model descriptions are included for simulation in programs like EZNEC, NEC-Win Plus, AO, or NEC4WIN.

Bill Orr W6SAI ham radio techniques. Improving ground connection, computer analysis of the antenna, modelling sample antennas pdf file

PA11019 Travel loop antennas, these antennas cover 6.300 to 29.200 mHz , handle 35 Watts and have a packing size of 43 cm, ideal for fieldwork, or mobile operations.

ON6MU Optimized 10 and 6 and 4 element UHF Yagi Antenna

Includes links and documentation on wifi antennas, 2.4 GHz Coffee Can Feed Antennas

Calculates precise dimensions for **Moxon rectangle** HF antennas, enabling hams to design antennas by inputting desired resonant frequency and wire diameter. This web-based tool, version 0.5, is a PHP front-end developed by W4/VP9KF, based on a public domain BASIC program originally authored by L. B. Cebik, W4RNL. It generates critical measurements for the driven element and reflector, ensuring proper spacing and element lengths for optimal performance. User feedback confirms the calculator's accuracy, with one user reporting resonance within 50 Hz of the design frequency for an 18 MHz antenna, eliminating the need for SWR adjustments. This contrasts with other online tools that resulted in significant frequency discrepancies. The tool's precision facilitates building **directional antennas** for specific bands, contributing to effective DXing and contesting operations.

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.

Constructing a linear focus parabolic antenna for WiFi operation involves precise metalwork, as detailed in this project. The author, AB9IL, shares a build that can be completed in a few hours, emphasizing the hands-on process of shaping and assembling metal components. This design aims to provide enhanced signal range for 2.4 GHz wireless networks, a common challenge in many ham shacks and home setups. The project outlines the practical steps required, from initial measurements to the final assembly, including cutting, bending, and bolting various metal parts. While specific gain figures are not provided, the parabolic design inherently offers significant _directional gain_ compared to omnidirectional antennas, making it suitable for point-to-point links or extending network coverage over distances. The construction process focuses on readily available materials and basic shop tools, aligning with the DIY spirit prevalent in amateur radio. This antenna project is presented as a straightforward build, requiring attention to detail in fabrication to achieve optimal performance.

The alternative multi-band solution, covers more bands than a G5RV, light weight, won't damage your trees.

Various tests and designs, with photos of home made EH Antennas,simple and networked, and also sone CAN Antennas.

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.

Theory, Modeling, and Practical Applications By W5JCK, presentation in PDF File. This presentation focuses on Near-Vertical Incidence Skywave (NVIS) antennas, which are crucial for short-range radio communications, particularly in military and emergency contexts. It explores NVIS theory, antenna models, and installation criteria while debunking common myths about reflectors. Key topics include usable frequency bands, optimal installation heights, and the impact of soil quality on performance. The presentation outlines the best bands for daytime and nighttime use, emphasizing the importance of understanding propagation characteristics to enhance communication effectiveness within 200 to 300 miles.

Manufacturer of Fibreglass Whip Antennas, Low and mediun Frequency, HF and VHF Antennas Specialized in the design and manufacturing of a full range of Beacon (MF), AM Broadcasting 540 - 1700 KHz, HF 1.7 to 30 MHz, VHF 30 to 156 MHz and UHF 200 to 500 MHz antennas.

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.

It consists of a group of JavaScript driven web pages that are intended for use as a quick reference for Ham Radio operators or just anyone interested in electronics. Offer calculators for Resistors, capacitors, inductors, power supplies, filters, attenuators and antennas

How slinky loaded beverage antennas works, includes eznec models

Determine the K-Factor used as a multiplier when constructing half-wave antennas.

Online shop based in hong kong offer batteries mic speakers adaptors programming cables earpieces telescopic antennas handheld antennas desktop chargers handheld speakers. Kenwood Icom Yaesu and Alinco dealer

Learn basic theory on antennas, and notes on homebrewing efficient shortwave antennas

Overview, summary, tutorial about the dipole antenna or dipole aerial that is widely used on its own and as the basis for other antenna designs.

There are lots of good designs for matching transformers for receiving antennas. Make it yourself it's cheap and easy, and very high performance. This is the design used in the TRX-9 transformers.

A 40 ft vertical dipole antenna that can cover HF Bands from 80 to 10 meters winding a dipole in a 12m HD telescoping fiberglass pole

This Arduino project decode ICOM CAT frequency information and switch antennas according to preset values. RX and TX antennas can even be different, a project by ON7EQ

The ARRL page, titled "The HF Mobile Antenna," serves as a curated index to various _QST_ articles focusing on constructing mobile HF antennas. It presents several projects for the mechanically inclined amateur, suggesting that homebrewed antennas can achieve efficiency comparable to commercial versions. For instance, one entry details a **five-band** antenna for RVs, utilizing a fold-over Hustler 4BTV, while another describes a "Bug Catcher" design for 80 through 10 meters. Further projects include a budget-friendly $20 HF mobile antenna made from PVC and wire, covering 20 through 6 meters, and the "Alpha Special," a multiband horizontal antenna originally for 1960s station wagons, now suggested for mini-vans. The resource also addresses antenna mounting solutions specifically for travel trailers and campers, providing practical insights for those operating from recreational vehicles. Rounding out the collection are the "Connecticut Longhorn," a 75-meter horizontal whip with remote tuning, and its redesign, the "Connecticut Shorthorn," adapted for smaller vehicles post-1970s. This compilation offers a historical perspective on mobile antenna innovation and practical construction guides for various HF bands and vehicle types.

Experiments by G8JNJ on wire antennas for low bands. Based on these tests, conclude that for multiband (160 to 6m) operation, in a restricted area it is very difficult to beat a G5RV, especially the ZS6BK version.

An homebrewed dipole antenna for 14MHz

A vertical antenna for the top band, made with a 26m fiberglass spiderpole by DJ0IP

The Homebase10 is a simple to make wire halo antenna for 10m (28MHz) built using parts available from the local DIY store.The resulting antenna is very effective on 10m despite its small size and light weight.

A circular waveguide calculator for designing cantennas include source code and windows executable by lincomatic

G4URH calculations to design your own antennas, ground plane, half wave antennas, Quad Antennas and 5/8 verticals

Manufacturers and distributors of coaxial surge protectors, coaxial switches, insultators, HF fixed wire antennas

Sirtel produces a wide range of radio and telecommunications antennas

Excel sheet containing technical comparisons of commercial HF portable antennas compiled by ON4SKY. Includes pictures, manufacturer, db gain, band coverage, F/B ratio, price, weight and dimensions.

Demonstrates a practical modification to convert a standard G5RV antenna into a _160-RV_ for effective operation on the 160-meter band. This project addresses the challenge of achieving Top Band resonance with a common multi-band wire antenna, providing a solution for hams with limited space or resources for dedicated 160m antennas. The design utilizes a specific length of 450-ohm ladder line and a 1:1 current balun, acting as a matching section to bring the G5RV's impedance into a usable range for 1.8 MHz. The document includes a parts list, detailed construction steps, and tuning instructions, emphasizing the importance of precise measurements for the ladder line and coaxial cable sections. It also outlines the expected SWR characteristics and power handling capabilities, making it suitable for QRO operation up to 1.5 kW. The _AD1B_ design offers a straightforward approach for extending the utility of an existing G5RV.

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.

Ham Radio Tower Project at N0HR. Includes site plan, escavation, tower construction, HF antennas, grounding and lightning protection, coax and more.

ARRL index of document about trapped antennas and notes on traps usage

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.

Presented here is a high-performance, circularly polarized omni-directional antenna that is easy to build, easy to tune, inexpensive, and will work all the mode J Low Earth Orbit (LEO) satellites

HF pedestrian operation using loop antennas by PY1AHD