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Build a space efficient trapped dipole antenna for 40-80-160 meter bands using RG-58 and PVC pipe. The document provides a brief guide on building a compact dipole antenna appropriate for the 40, 80, and 160-meter amateur radio bands. It explains the materials, building processes, and tuning methods required to provide best performance while preserving space. The paper also discusses theoretical elements of dipole antennas, such as impedance matching and feedline selection.

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.

This resource provides a detailed guide on constructing a J-pole antenna specifically for the 2 meter band, which is popular among amateur radio operators. The article outlines the materials needed, including various sizes of aluminum pipes and PVC, as well as the tools required for assembly. It emphasizes the simplicity and effectiveness of the J-pole design, making it an ideal choice for newcomers to amateur radio. The instructions are straightforward, allowing users to build the antenna in less than an hour, and include tips for tuning the antenna for optimal performance. In addition to the construction details, the resource includes practical advice on the assembly process, such as how to cut and join the pipes, as well as how to mount the SO239 connector. The author shares personal experiences and insights on achieving a low standing wave ratio (S.W.R.) and suggests modifications for creating bi-band or tri-band J-pole antennas. This comprehensive guide is enriched with photographs that illustrate the construction steps, making it easier for users to follow along and successfully build their own J-pole antenna.

Cubic quad antennas are renowned for their high gain, excellent front-to-back ratios, and low angles of radiation, making them a popular choice among amateur radio operators. This resource provides detailed designs for constructing cubic quads optimized for 2, 6, 10, 12, and 15 meter bands. The lightweight structure can be easily built using fiberglass tubes and central hubs, allowing for portability and ease of assembly. The article discusses the specific dimensions and configurations required for both HF and VHF applications, emphasizing the importance of proper spreader lengths and boom dimensions. It also highlights the challenges of assembling larger cubic quads in limited spaces, offering practical solutions for hams with smaller backyards. With a focus on multi-band operation, this guide serves as a valuable resource for both novice and experienced operators looking to enhance their antenna systems.

The 160/80m coaxial receiving loop antennas are designed to enhance reception on the top bands while minimizing noise. These antennas are particularly beneficial for operators with limited space, as they can be constructed using lightweight materials, making them portable and easy to deploy. The standalone 80m loop has a diameter of approximately four feet, allowing for easy rotation and installation above existing VHF antennas. Over the years, many amateur radio operators have turned to loop antennas as a viable alternative to traditional beverage antennas. The design allows for significant noise reduction, especially when paired with a quality pre-amplifier. Experimentation with various configurations has led to the discovery that diamond-shaped loops provide optimal performance. Users have reported a noticeable improvement in signal quality, making these loops a valuable addition to any low-band DXing setup.

This resource provides comprehensive instructions for constructing a 2 element quad antenna specifically designed for the 10, 12, and 15 meter bands. The antenna features a diamond configuration, which offers improved gain compared to a square configuration. The author shares insights into the materials used, including a square-aluminum boom and bamboo poles, along with construction techniques that ensure durability and optimal performance. This project is ideal for amateur radio enthusiasts looking to create their own antennas at home. In addition to construction details, the author discusses the antenna's performance, noting its effectiveness even at a height of 8 meters. The quad antenna reportedly performs comparably to a 3 element yagi, with excellent SWR readings and strong signal reports from European stations. This project is suitable for beginners and offers a cost-effective solution for those interested in enhancing their amateur radio setup with a homemade antenna.

Building details of a VHF colinear antenna with 6 db gain

Author evaluated a custom-built passive AM loop antenna, achieving notable DX reception including KLBJ Austin (230 miles) and WWL New Orleans (700 miles). The antenna operates solely on resonant inductive coupling, enhancing weak signal reception without external amplification. This project illustrates how fundamental RF design—calculating inductance, capacitance, and Q factor—can significantly boost performance of consumer-grade radios. Detailed construction techniques, theoretical background, and optimization strategies for effective loop antenna design are presented for amateur and experimental use.

The page provides detailed plans and pictures of 80m and 160m antennas for both transmission and reception, emphasizing the importance of antenna farm on low bands. It discusses the differences between TX and RX antennas, the significance of signal-to-noise ratio, and the benefits of directional antennae. The author shares personal experiences and recommendations for successful operation on low bands.

Complete guide to build Jpole antennas with online dimensions calculator.

This resource details the fundamental aspects of deploying longwire antennas, emphasizing ease of construction and installation for shortwave listening (SWL) and broadcast reception. It covers wire gauge selection, suggesting 14 to 24 AWG for general use, with heavier gauges (14-20 AWG) for permanent outdoor installations. Guidance is provided for various deployment scenarios, including indoor setups where the wire can be run around a room, temporary outdoor installations from balconies using light 18-24 AWG wire, and permanent outdoor configurations requiring higher placement and slack for tree movement. Feeding methods are discussed, recommending coaxial cable (50-75 ohms) to mitigate man-made interference, with instructions for connecting only the center conductor to the longwire. Safety precautions are highlighted, particularly avoiding contact with power lines and conductive materials, and managing static electricity buildup by unplugging the antenna after use and bleeding off charges before connection. The article also advises against using outdoor longwires during thunderstorms or snowstorms due to static and lightning risks. Optimal height considerations are presented, advocating for the highest safe placement, ideally a couple of feet above underlying structures, to maintain free air space. The text mentions a personal setup with one end at a roof peak (20 feet) and the other at a 17-foot mast, illustrating practical deployment without strict height requirements beyond safety and clearance.

2-Element parasitic Yagis for the Shortwave-Bands 10-12-15-17-20-30m. The antennas are feeded with the DK7ZB-match. A quarter-wave choke of coax is grounded at the socket.

Demonstrates the construction of **magnetic loop antennas**, detailing both multi-turn and single-turn designs. It covers a 30-inch diameter multi-turn loop for 80 meters, based on a February 1996 QST article, and an octagon single-turn loop made from 15mm copper tube with a 4.8-meter circumference, operating from 7 MHz to 14 MHz. The document also presents a smaller 800mm diameter loop for 14 MHz to 28 MHz, emphasizing the importance of high-voltage tuning capacitors. Covers the design and construction of custom **butterfly capacitors** and piston capacitors, including a split stator capacitor with 140 pF capacitance and a 6000 Volt rating, and a butterfly capacitor with 5-65 pF and 7200 Volt rating. It explains why butterfly capacitors are preferred over split stator types for high power applications due to lower losses and direct series connection of rotors, reducing resistive losses from wiper contacts. Material recommendations include clear PVC for plates and brass or stainless steel for non-magnetic hardware. Addresses practical considerations such as feeding the loop with a shielded 1/5 Faraday loop made from RG213 or RG8 coax, achieving VSWR 1.1 across bands, and optimizing its placement 180° from the capacitor. It also discusses mechanical joint resistance, dissimilar metal oxidation prevention using Vaseline, and a simple method for determining radiation angle with a TL-light tube. The guide includes diagrams for rotor, stator, and end plate construction.

The **Extended Double Zepp** (EDZ) antenna, a simple wire design, is presented as a means to achieve 3-4 dB of gain on 10 meters, with an overall length of just 43 feet. This resource, authored by WB3HUZ, details several gain antennas suitable for the 29 MHz AM segment, all modeled using EZNEC software at 30 feet above ground. Other designs include a compact rectangular loop, offering more gain than the EDZ and a lower take-off angle, and the **Lazy H**, a bidirectional antenna providing 6 dB gain, which is also workable on 20, 17, 15, and 12 meters. The Bisquare, a diamond-shaped open-top loop, is also featured, providing approximately 4 dB gain and requiring only a single support. These designs are primarily fed with ladder line or open-wire line to simplify matching, though a coax feed option for the EDZ is shown for 10-meter-only operation. The Lazy H, for instance, requires about 16 feet of open-wire line for its half-wavelength elements spaced a half-wavelength apart. An enhanced EDZ Lazy H variant is also discussed, achieving an additional 1-2 dB gain by extending element length to 1.28 wavelengths and increasing spacing to 0.64-0.75 wavelengths. The Bisquare, while primarily a 10-meter antenna, can be adapted for 20 meters by closing the top connection.

RM is an Italian company operating in the radio communication field since 1974, main products are: HF-CB-VHF-UHF-Dual Band RF Power Amplifiers, Power Supply, DC-DC Converters Antennas and more products.

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**.

The Pfeiffer Maltese Quad Antenna System presents a unique approach to traditional quad antennas by utilizing a linear loading technique. This method effectively reduces the overall size of the antenna while maintaining its performance capabilities. Designed by Andrew Pfeiffer, the antenna's configuration resembles a Maltese cross, which not only enhances its structural integrity but also allows it to withstand challenging environmental conditions. This system is adaptable, offering various configurations from a 4-spreader Maltese Quad to a 16-spreader Maltese Quadruple-Cross, making it suitable for operators looking to optimize their setup without sacrificing efficiency. This antenna system is particularly versatile, covering multiple bands including 40, 20, 17, 12, and 10 meters. The design focuses on minimizing the physical footprint while ensuring effective signal transmission and reception. Amateur radio operators can benefit from the detailed plans available in the accompanying PDF, which outlines the construction process and specifications. Whether you're a seasoned DXer or a newcomer to the hobby, the Pfeiffer Maltese Quad Antenna System offers a practical solution for enhancing your station's capabilities.

Short guide to home made antennas for shortwave reception, in pdf format

This is a custom home made antenna, based on concept of commercial HF antennas, that may work on 160 meters too.

Force 12 HF and VHF antennas, aluminim towers and masts for ham radio

Antenna Restrictions, Power Restrictions, RFI Problems, or Limited Space keeping you off the air?

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 RockLoop Antenna is a compact multiband portable and indoor antenna suitable for QRP operations on the 10, 14, and 21 MHz bands. The page provides detailed information on the design and usage of this antenna, making it a valuable resource for amateur radio operators looking to improve their setup. The intended audience is amateur radio operators interested in building and using antennas for QRP indoor operations.

How to construct a very small but efficient Antenna with PVC Plumbing tube and discarded fruit cans. - Just the thing to fit in a small space such as the house attic

The Cubical Quad antenna is a popular choice among amateur radio operators due to its robust design and excellent performance characteristics. This resource provides essential scaling formulas that help determine the lengths of the antenna elements and the necessary gamma match values for various frequencies. The design is adaptable, allowing operators to optimize for gain or front-to-back ratio by adjusting the spacing between elements. The accompanying Excel files facilitate precise calculations, making it easier for both beginners and experienced hams to construct their own Cubical Quad antennas. In addition to the design formulas, the resource includes practical insights from the author, who has successfully built and utilized these antennas in various field events. The document outlines the tuning process for achieving minimum VSWR, ensuring optimal performance. With detailed illustrations and performance data, this guide serves as a comprehensive reference for anyone looking to delve into Cubical Quad antenna construction and optimization, enhancing their amateur radio experience.

The page provides a tool to create a customized Ham Radio Az Map on the fly, with various dimensions available. It is a valuable resource for amateur radio operators to visualize and optimize pointing of directional antennas. The content includes maps for different regions, prefix maps, and world maps.

The page describes two types of 2 meter J-Pole antennas, one made of copper pipe and a roll-up J-pole made of TV twin lead, providing dimensions, components, and construction details. It is authored by Dr. Carl O. Jelinek N6VNG.

All these plans use the DK7ZB match

The website https://www.qsl.net/dl5dbm showcases homebrew projects related to KW, 2-meter, 6-meter, antennas, amplifiers, preamps, power supplies, and more. It provides information and resources for radio amateurs interested in DIY projects and experimentation.

End-Fed Half-Wave Antenna for the 7 or 10 MHZ amateur bands intended to provide a very simple to erect yet effective portable QRP antenna.

Attic antennas can work better than you might think, some of mine work as well as their outside counterparts

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.

This article describes how an effective ground system can be produced for a short vertical antenna.

Two well performing 50 MHz antennas designed with W7EL EZNEC along to many other antenna projects and related articles

NGC is now distributor for COMET and MALDOL brand antenna products designed, manufactured in Japan. Distributor of DAIWA brand RF SWR/power meters and switching power supplies, antennas, test equipment, antenna analyzers and more

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.

Homebrew VHF Yagi 50MHz 144MHz 432MHz 1296MHz 2320MHz 6M 2M 70CM 23CM 13CM Yagis

Low weight Titanium Verticals, Log-Periodics, Yagi antennas, Quads, towers and antenna accessories by Titanex

This Vertical antenna design by David Reid for lower bands focuses on achieving effective DX communication by optimizing the antenna low-angle radiation for long-distance contacts. The design incorporates techniques like linear loading and capacity hats to reduce the antenna's height while maintaining performance, especially on 40m and 80m bands. Building a solid ground plane and using quality materials ensure efficiency and durability. Although vertical antennas can be complex to build, this project simplifies the process, making it accessible for ham operators seeking strong, reliable signals.

How High should my Dipole be? Dipole Antennas and the effect of height above ground. The effectiveness of a dipole antenna is influenced by its height above ground, determined by the intended use such as DX work, local communication, directionality, omni-directionality, and feed point impedance. Through EZNEC modeling, the study evaluates a 40-meter dipole's performance at various heights, from 7 to 560 feet. Findings reveal that lower heights enhance omni-directional local communication, while higher placements favor DX work with low-angle radiation. The study emphasizes the importance of defining operational goals to optimize dipole height and performance.

K9AY loop antenna installed at PA6Z Contest group. This is a receiving antennas for the low bands (160m, 80m and 40m). Include schematics and info on a building the control box, preamplifier and low-pass filter

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.

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.

Javascript for calculating the lengths of tubing to be used for the construction of a Super J-Pole in a collinear design

An efficient program to calculate dimensions of coax dipoles, or bazooka antennas considering velocity length of different coax cables. Express dimensions in feet/inch and meters/cm. Freeware by VE3SQB

How to build a beverage antenna. How to deploy a BOG antenna for your next SWL DX-ing activity. Give it a try and follow the orientation tips for this bi-directional antenna.

Types of beverage wires, choose best supports and insulators, multiple antennas at one feedpoint, all well documented with photos and exaustive explanation. This article offers insights on building Beverage antennas for optimal reception. Key takeaways include using strong wire (copperweld or electric fence), proper termination, and a good grounding system (multiple copper rods). The author recommends maximizing antenna length and orienting it towards desired stations. For best results, utilize an antenna tuner and experiment with termination resistors.

A 1.5-meter telescopic whip antenna project for the Yaesu FT-817 QRP transceiver is presented, offering a cost-effective alternative to commercial portable antennas like the Whip Miracle. The design incorporates a **toroidal matching unit** with a rotary switch for band selection and a toggle switch for fine-tuning the coil taps. This setup allows operators to achieve a low **Standing Wave Ratio (SWR)** across various HF bands, despite the inherent limitations of a physically short radiator on lower frequencies. The construction details include photographs of the completed unit, showcasing the compact enclosure and the integration with the FT-817. A simple schematic illustrates the coil tapping arrangement and the switching mechanism, guiding hams through the assembly process. The project emphasizes practical, portable operation for **QRP** enthusiasts, acknowledging that while performance on bands like 80m or 40m will be modest, it can still facilitate contacts under favorable conditions with skilled operation.