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Demonstrates the construction of a **multi-band HF mobile antenna** utilizing a modified CB whip antenna base. The resource details the process of stripping a commercial CB whip, winding a new helical coil with 0.7mm insulated copper wire, and identifying tapping points for various HF bands. It emphasizes the importance of a rugged, slim design for mobile operation, discussing mechanical length, power handling (up to 200 watts), and coil diameter considerations. The article includes a graphic illustrating the antenna's operational principle, where sections of the helical coil are shorted from bottom to top to maintain efficiency and high Q. The resource presents a practical approach to achieving **band switching** without an external tuner, by manually adjusting tapping points on the coil. It provides a table with reference lengths in centimeters from the feedpoint for 7 MHz (40m) through 28.7 MHz (10m), including WARC bands. The author details mounting techniques, suggesting a Diamond bracket for secure attachment to a vehicle trunk, and stresses the critical role of proper grounding for optimal performance. The design allows for operation on 75m and 80m bands by adding a 110mm steel whip.

Low noise, receive only coax loop antennas for 160 - 10 meters HF bands

Constructing a 2-meter 5/4 wave antenna, N1HFX details a design fully enclosed within 3/4-inch PVC tubing, addressing the significant velocity factor of PVC which necessitates a 19% reduction in physical length. The design incorporates a specific matching system using 300-ohm TV twin lead to counteract the highly inductive impedance component inherent in a 5/4 wave radiator. Key components include #18 stranded insulated wire for the radiating element, RG58/U coax, a PL259 connector, and a hardwood dowel for internal support, all carefully dimensioned for optimal performance within the PVC housing. The article provides precise cutting lengths for the twin lead and #18 wire, with the overall assembly measuring 77 3/4 inches, reflecting an approximate velocity factor of 0.81. Tuning instructions emphasize taking SWR readings with the antenna assembly inside the PVC, adjusting the #18 wire and twin lead in small increments to achieve a low SWR across the 2-meter band. The prototype antenna achieved SWR readings below 1.2:1 across the entire band, and N1HFX suggests an estimated 6 dB gain when properly mounted, offering a cost-effective alternative to commercial antennas.

Schema of a self made balun used to match randmon wire antennas, mainly for shortwave listening pourposes, in italian

The HB9ABX mobile HF antenna, developed by _Felix Meyer_, offers a high-performance alternative to commercial mobile antennas for 80 through 10 meters. Constructed from fiberglass rods and enamelled copper wire, this design incorporates a loading coil with multiple taps, allowing for band-specific tuning. The article provides detailed instructions for winding the coil, connecting the antenna elements, and integrating it with a vehicle's chassis ground. Field tests conducted at 100W consistently showed the HB9ABX antenna outperforming a HUSTLER mobile antenna by up to **10 dB** (1 S-point) and a YAESU ATAS-100/120 by **18 dB** (2-4 S-points) across distances from 5 km to 1000 km. The design emphasizes a robust ground connection and the use of an antenna tuner, such as an _MFJ-901B_, for optimal SWR on all bands, particularly 40 and 80 meters. Initial adjustment involves setting whip length and coil tap positions to achieve resonance without a tuner, followed by fine-tuning with the tuner during operation. Specific measurements are provided for checking resonance on 21.0 MHz and 14.2 MHz, with precise turn counts for the lower (79 turns) and upper (120 turns) antenna sections. Safety precautions for handling fiberglass dust are also highlighted.

The RXO Unitenna, a vertical wideband antenna, offers operation across the 7-21 MHz spectrum, covering the 40, 30, 20, 17, and 15-meter amateur bands. This design focuses on achieving a low SWR across a broad frequency range, making it suitable for general HF operation without requiring an external antenna tuner for minor SWR variations. The antenna utilizes a unique loading coil and matching network to maintain efficient radiation characteristics across its operational bandwidth. Construction details within the PDF document include specific dimensions for the radiating element and the counterpoise system, which is critical for vertical antenna performance. The design incorporates readily available materials, simplifying the build process for radio amateurs. Performance graphs illustrate the SWR characteristics across the 7 MHz to 21 MHz range, demonstrating the antenna's wideband capabilities. The document also provides guidance on feedline connection and grounding considerations for optimal field deployment. This vertical antenna configuration is particularly useful for hams with limited space, offering a compact footprint compared to horizontal wire antennas.

Demonstrates a **shunt-feed** matching technique for Hustler mobile HF antennas, specifically the MO-3 mast with RM series resonators, to achieve optimal **SWR** on the 40-meter and 20-meter bands. It details the construction of a loading coil using 20 turns of #12 solid wire, 1.25-inch ID, spread to 5 inches, and provides tap points: 8 turns for 40m and 4 turns for 20m, connecting one end to the feed point and the other to ground. The resource presents specific SWR results, noting a 1:1 match at 7.258 MHz on 40m and 14.275 MHz on 20m, with SWR remaining below 1.5:1 across significant portions of the General phone segments. It highlights a noticeable improvement in both transmit and receive performance compared to a straight antenna setup, emphasizing the practical application of this matching method for mobile installations, particularly on a fender-mounted ball mount.

Normal mode helix antennas offer a solution for HF mobile operators facing significant height restrictions, such as those parking in indoor garages with limited overhead clearance. This design, adapted from concepts typically applied to VHF/UHF rubber duck antennas, allows for extremely shortened HF radiators that remain effective for county hunting and general mobile operation. The resource details the construction of a 20-meter helix antenna, approximately 10 inches long, wound with #14 AWG THHN wire on a 1 1/2-inch CPVC form, mounted on a standard 3/8 x 24 antenna stud. Mark Herson, _N2MH_, shares his experience developing these antennas, including initial research from the _RSGB VHF UHF Manual_ and practical winding experiments to establish the relationship between turns and resonant frequency. He provides coil data for various frequencies, emphasizing that these measurements were taken with an _MFJ-259a_ antenna analyzer and are dependent on the vehicle's grounding system. Despite their shortened nature, N2MH confirms the antennas' operational effectiveness, citing contacts with KL1V in Alaska on 20 meters and E-skip contacts on 10 meters. The design prioritizes continuous deployment without removal, making it suitable for operators who frequently navigate height-restricted environments.

Another approach to hidden HF antennas

manufactures and distributes HF, VHF, UHF and SHF equipment covering 10MHz. - 47.0GHz. Our products include: Wireless LAN / WAN Bidirectional Linear Amplifiers, Low Noise Preamplifiers - LNA's, RF Linear Amplifiers, Relays, Transverter Systems, Frequency Translation Systems, Downconverters, Antennas, Parabolic Dishes, Coaxial Cable, Relays, Antenna Switches, Microwave Test equipment, PC controlled Receivers, Microwave Linear Amplifiers including models for Telemetry, Wireless, and CDMA applications.

WB2VUO presents a practical examination of effective HF mobile antennas, focusing on the inherent efficiency challenges encountered on the lower bands, specifically 160, 80, and 40 Meters. The resource delves into the necessity of loading coils for mobile operation below 21 MHz, where full-sized antennas are impractical. It contrasts base-loaded and center-loaded designs, noting that base-loaded antennas are simpler for the average ham to construct but offer lower efficiency compared to center-loaded configurations. The author provides specific data for an 8-foot whip, detailing its electrical length and _radiation resistance_ across various HF bands, from **0.08 ohms** on 160 Meters to **16.1 ohms** on 12 Meters. This data highlights the extremely low radiation resistance on lower frequencies, which significantly impacts feedpoint impedance due to ground and feedline losses. The discussion includes practical considerations for feedpoint impedance, noting that a typical 8-foot whip on 10 Meters might present 30-45 ohms, allowing for acceptable SWR without an ATU. Construction sketches illustrate both base-loaded and center-loaded mobile antennas, with advice on material selection like galvanized steel for rugged bottom sections. The article also includes coil value charts from the _ARRL Mobile Manual_ for both base and center loading, emphasizing the importance of using large diameter wire to minimize losses and suggesting capacity hats to reduce coil inductance and improve performance on 160-40 Meters.

Examines the operational principles of loading inductors within **mobile HF antennas**, clarifying their role in canceling capacitive reactance rather than physically replacing missing antenna length. It meticulously details how current distribution is influenced by stray capacitance and termination impedance, rather than the physical length of wire within the coil itself. The resource provides a deep dive into the behavior of inductors, emphasizing that a loading coil functions identically to any other inductor in an electronic circuit, with its characteristics determined by its design and surrounding impedances. This article specifically addresses common misconceptions, such as the idea that loading coil current is reduced by standing waves or that coils introduce a significant electrical-degree phase delay related to conductor length. It explains that magnetic flux coupling within the coil causes charges to move at light speed, resulting in minimal time delay across the inductor, especially in well-designed, compact units. The author, W8JI, presents both theoretical explanations and empirical measurements to support these points, including data from various antenna configurations. Furthermore, the content clarifies the distinction between voltage-current phase shift within an inductor and actual current time delay through it, using **SPICE models** and real-world observations. It highlights that large current taper in a loading coil often indicates poor antenna or tank circuit layout, rather than an inherent property of the inductor itself. The discussion also touches on the impact of stray capacitance on inductor Q and bandwidth, offering insights into optimal form factors for different applications.

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.

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.

RF Choke to prevent hf currents on the feedline. This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

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.

How to create a simple but effective half wave dipole, illustrated instrucions on how to build wire antennas

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.

This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

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

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.

Planning and modelling Delta Loop antennas for all the ham radio HF bands include calculated wire lengths at each mid-band

The PDF document, titled "J-Poles," presents various J-pole antenna designs covering the 50 MHz to 450 MHz frequency range. It includes construction details for several specific bands, such as a 6-meter J-pole, a 2-meter J-pole, and a 70-centimeter J-pole. The content outlines the fundamental principles of J-pole operation, including the quarter-wave radiator and half-wave matching stub. Each design features specific dimensions for elements like the radiator length, stub length, and spacing, often expressed in inches. The document also discusses feeding arrangements and impedance matching considerations inherent to J-pole antennas. It provides practical guidance for homebrewing these antennas using common materials like copper pipe or wire elements. The resource offers insights into the advantages of J-poles, such as their omnidirectional pattern and ease of construction, making it a practical reference for radio amateurs interested in VHF/UHF antenna projects.

About HF Wire Antennas for field day or any day a basic wire antenna article

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

Designers and manufacturers of radio Frequency antennas. HF - 3000 MHz TET Emtron HF Yagis, Antennas for Wireless applications, Marine antennas, Land mobile, Mobile antennas.

The G5RV multiband HF antenna, designed by Louis Varney (G5RV) in 1946, is a popular compromise antenna offering good overall performance on most HF bands when paired with an external antenna tuner. The basic full-size G5RV measures 102 feet across the top for 80 through 10 meter operation and is fed at the center via a 34-foot low-loss feed-stub. This interaction between the radiating section and the feed-stub facilitates matching across 80-10 meters with a standard tuner, often eliminating the need for ladder line directly to the shack. The antenna's design center frequency is 14.150 MHz, configured as a 3/2-wave dipole on 20 meters, with its 102-foot length derived from long-wire antenna formulas. Construction details emphasize the matching section, which can be open wire, ladder line (window-type), or TV twin lead. Each type has a specific velocity factor (VF) affecting its physical length for an electrical half-wave on 14 MHz; for instance, open wire requires 33.7 feet (VF 0.97), ladder line 31.3 feet (VF 0.90), and TV twin lead 28.5 feet (VF 0.82). The article provides formulas for calculating these lengths and discusses the antenna's behavior on individual bands, from 3.5 MHz where it acts as a shortened dipole, to 28 MHz where it functions as two three-half-wave long-wire antennas fed in-phase. Practical construction notes include recommendations for vertical descent of the matching section, sealing the coax junction, providing strain relief, and winding a coaxial choke coil to mitigate common mode current. The resource also presents dimensions for double-size (204 ft) and half-size (51 ft) G5RV versions, along with their corresponding matching section lengths for various line types, making it a versatile reference for hams considering this classic wire antenna.

Demonstrates the construction of a _3MA triband mobile antenna_ designed by IZ7DJR, emphasizing a full-size quarter-wave whip for 10 meters. The design incorporates a rapid tilt-down mechanism to facilitate quick changes of loading coils for operation on 15 and 20 meters. This approach aims to minimize losses and enhance efficiency compared to conventional base-loaded mobile antennas. The resource provides specific coil winding data: 22 turns for 15 meters and **37 turns** for 20 meters, both using 1mm wire over an 80mm coil length. The 10-meter band operates without a loading coil, leveraging its full-size design. The author's design prioritizes ease of band switching and improved performance for mobile HF operations, offering a practical alternative to more lossy commercial options.

Using our components you can build a rotating tower with greater capability than 3-4 static towers. A rotating tower allows common rotation of HF stacked arrays, VHF and UHF arrays, and antennas mounted at optimum heights. Component design also allows tower shunt loading and end support for wire antennas

This resource details the construction of a portable antenna tripod designed for supporting small vertical antennas, utilizing readily available electrical metal tubing (EMT) or conduit. It outlines the necessary components, including a custom-fabricated _EARC tripod plate_, standard hardware, and a 10-foot section of 1/2-inch EMT cut into specific lengths for legs and a center support. The instructions cover assembly of the tripod plate, leg construction, and integration with a fiberglass fishing pole like the _Kwik Stix_ or _Shakespeare Wonderpole_ to support a vertical wire HF antenna. The project also describes an adaptation for using the tripod with 3/8x24 threaded mobile antennas such as _Hamsticks_ or _Buddisticks_, where the tripod structure itself contributes to the antenna's counterpoise system. A complete parts list is provided, along with ordering information for the specialized EARC tripod plate, which serves as a fundraiser for the Honolulu Emergency Amateur Radio Club. The document includes photos illustrating the assembled tripod and its use with a fiberglass pole.

Designing and constructing portable wire antennas for HF operations, this resource explores several configurations including the _foldback dipole_ for space-constrained setups and an inductively shortened dual-band dipole for 20m and 40m. It details the calculation of inductance for shortened elements, providing a Visual Basic 6.0 program screenshot that illustrates determining coil parameters like turns and length for a **25.5 uH** inductor. The document emphasizes practical considerations such as adjusting wire lengths for optimal SWR, noting that a dual-band dipole achieved SWR below 2:1 on both 20m and 40m, with careful adjustment bringing it under 1.5:1. Further, the resource describes a half-wave antenna matched with a coaxial stub, a method often referred to as the _Fuchskreis_ in German amateur radio circles, to transform the high feedpoint impedance to 50 Ohms. This monoband solution, for a 20m application, uses a stub length of **2.98m** (0.216 lambda multiplied by coax velocity factor) and a shorted stub of approximately 48cm. The coaxial stub design is highlighted for its resilience to ground proximity, allowing it to be rolled up or laid on the ground with minimal SWR impact, making it highly suitable for portable QRP operations.

My Top Five Backyard Multi-Band Wire HF Antennas. A selection of the top 5 HF wire antennas for the backyard and for multi-band operation

DK7ZB's fan dipole designs address the challenge of operating multiple HF bands with a single feedline, providing practical construction details for **multiband wire antennas**. The resource outlines specific lengths for half-dipoles across various band combinations, including 10-15-20m for classic bands and 12-17-30m for WARC bands. It emphasizes the importance of proper spacing between resonant elements to avoid impedance interaction and high SWR, a common issue when frequencies are too close. The article details the use of **current baluns** built with FT240-43 or FT140-43 cores, specifying turns and cable types for 1KW and 400-Watt power levels. It includes a correction table for adjusting dipole lengths based on frequency shifts, aiding in fine-tuning resonance. The 20+40m dipole is noted for its ability to operate on 15m with an ATU, demonstrating versatility.

Ten essential tips and truisms for understanding HF antenna: Non-resonant wire dipole antennas fed with open-wire line and an antenna tuner can function effectively as multiband antennas, as detailed in "The Classic Multiband Dipole Antenna" by WB8IMY in March 2004 QST. Coaxial cable, unlike balanced parallel-wire feed lines, can cause RF to travel on the outer shield braid, leading to RF feedback to the station; a 1:1 balun at the dipole center can mitigate this by isolating the unbalanced coaxial feed line. Antenna gain is achieved by shaping and directing RF energy, with beam antennas concentrating power in a specific direction, and wire antennas also exhibiting shaped radiation patterns. An antenna tuner's primary role is to match the transceiver's 50-ohm output to the antenna system's impedance, allowing modern transceivers to deliver full power. Wire antennas do not always require center feeding; end-fed long wires or off-center-fed dipoles (like the Windom) can be used, though they often necessitate an antenna tuner and a counterpoise or radial network. Dipole antennas do not need to be perfectly horizontal; their legs can be bent or inclined, which affects feed point impedance and may require SWR experimentation with coaxial feed. Vertical antennas shorter than a half wavelength require an efficient ground system, typically comprising elevated or buried radial wires, with more radials generally leading to better efficiency. A 1:1 SWR indicates an impedance match but does not guarantee antenna efficiency; an inefficient vertical antenna with a poor ground system can show a low SWR while wasting most RF as heat. Investing in high-quality, low-loss feed line, especially coaxial cable, is crucial for maximizing RF signal transfer and overall antenna system performance.

A 17 3/4-inch radiating element and 18 3/4-inch ground plane radials form the basis of this quarter-wave ground plane antenna for 2 meters FM. The design, attributed to AA1PG, utilizes a panel-mount SO-239 UHF connector and three lengths of #12 copper wire, with a total material cost estimated at $3.00. Construction involves soldering the elements directly to the SO-239, emphasizing thorough solder flow for robust connections. Recommended feedline includes _RG-8X_ for longer runs, with _RG-58_ acceptable for shorter lengths, cautioning against _RG-174_ for VHF applications due to high loss. The antenna is designed for elevated deployment, such as in trees or on roof gables, to maximize line-of-sight propagation. It aims to improve repeater access compared to typical rubber duck antennas, even with low power output.

This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

A collection of drawings of most popular wire antennas for hf ham radio bands

HF Beam Calculator for Amateur Radio and CB Communications

AD7DB discussion about HF wire antennas

The TransWorld Antennas TW4040 The Adventurer Monobander™ is a portable HF antenna designed for rapid deployment in field operations, including **SOTA** and **POTA** activations. This manual details the antenna's assembly, tuning procedures, and operational guidelines for optimal performance on the 40-meter band. It outlines the specific components, such as the telescoping whip and base unit, required for proper setup. Instructions cover mast erection, radial wire deployment, and impedance matching to achieve a low **VSWR** across the designated frequency segment. The document also provides guidance on antenna orientation and environmental considerations for portable use. It specifies the antenna's power handling capabilities and physical dimensions when fully deployed and collapsed for transport.

Presentation about Practical Antenna Modeling Using the NEC Codes with examples of HF wire antennas and 4NEC2. How to define and edit the models, Running the simulations, Work some examples, Variables usage, Deal with Feed Lines and ground

The OZ1CX center-loaded mobile antenna project details the construction of a compact **80-meter** antenna, specifically designed for mobile, portable, and stationary operations. It features a loading coil wound on a 50 mm PVC pipe with 1.5 mm copper wire, comprising 100 turns over 150 mm length, resulting in an inductance of 150 µH. The design incorporates a 1.5-meter whip and a 1.5-meter base section, with the coil positioned at the center for optimal performance on the 3.5 MHz band. Performance measurements indicate a **VSWR** of 1:1.2 at 3.7 MHz when mounted on a vehicle, achieving a bandwidth of 30 kHz for VSWR below 1:2. The antenna's efficiency is compared to a full-size dipole, showing a signal strength reduction of 3-4 S-units, which is typical for compact mobile HF antennas. Practical application notes cover tuning adjustments by varying the whip length and coil tap points, emphasizing the importance of a good ground plane for effective operation.

Antennas manufacturer based in Germany produce portable and wire HF VHF antennas

Aerial 51 is an antenna manufacturer producing HF Wire antennas. Their antenna product catalog includes portable, OCF wire antennas for HF bands but also QRP transceivers, and accessories for portable operations.Based in Germany

Amateur radio antennas manufacturer based in Italy. Produces HF end-fed, dipoles, and other wire antenna types, mono band and multi band antennas.

Founded in 1990, Nearson, Inc. has been providing our customers with exceptional value with the products and services we offer. VHF, UHF mobile radios, Cellular, PCS equipments as well as ISM band wireless data and WLAN applications.

Constructing an End-Fed Half-Wave (EFHW) antenna offers a practical solution for HF operators seeking a multiband wire antenna without the need for extensive radial systems. This design typically employs a high-impedance transformer at the feed point, matching the antenna's inherent high impedance to a 50-ohm coaxial feedline. The article specifically details a 2012 approach, focusing on a transformer with a 49:1 turns ratio, which is a common configuration for EFHW antennas. The resource outlines the construction of a wire element cut for a half-wavelength on the lowest desired band, with specific coil arrangements enabling operation on harmonically related bands such as 40m, 20m, and 10m. It discusses the physical dimensions and winding details for the matching transformer, often utilizing a ferrite toroid core to achieve the necessary impedance transformation. The content provides insights into the operational principles and practical considerations for deploying such an antenna, including methods for tuning and optimizing performance across multiple amateur radio bands. While acknowledging that the presented information from 2012 may be superseded by newer insights, it serves as a foundational reference for understanding EFHW antenna theory and construction.

The page provides information on a simple 50MHz J-Pole Antenna project based on the DK7ZB design. It explains the principle of the Wireman-J-Pole, the feeding process, practical mounting, and simulation results using MMANA GAL. The content aims to guide amateur radio operators in building their own J-Pole antennas for the 6-meter band.