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A 2 meter (146 Mhz) J-Pole antenna that is inexpensive, and easy to build.

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.

Build Your Own Bazooka Dipole: A VHF/UHF vertical dipole made from coax

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.

Home made vertical antenna for 80 40 15 10 meters ARRL PDF file taken from QST June 1978

Building a 2.4GHz vertical collinear omnidirectional antenna

This guide provides step-by-step instructions for constructing a tin can waveguide antenna, commonly known as a cantenna, for enhancing WiFi signal range. The project is budget-friendly, costing under $5, and utilizes easily accessible materials like a food can and basic electronic components. The design is suitable for 802.11b and 802.11g wireless networks, operating within the 2.4 GHz frequency range. To start, gather the necessary parts including an N-Female chassis mount connector, nuts, bolts, and a suitable can. The assembly process involves drilling holes in the can for the connector and mounting the probe. The guide emphasizes the importance of can dimensions and placement for optimal performance, encouraging experimentation for best results. This project is ideal for amateur radio operators and DIY enthusiasts looking to improve their wireless connectivity without significant investment. Safety precautions are advised, as the author does not hold electrical engineering credentials. Users are encouraged to take responsibility for their equipment and ensure proper assembly. With this simple yet effective antenna, users can extend their WiFi coverage and enjoy enhanced connectivity.

Schematics plans by K9GDT and all infos to build a 600 Watt HF Amplifier. The amplifier uses four Motorola MRF150 50 volt TMOS power FETs configured in push-pull/parallel and biased for class AB linear operation.

A home made J-Pole antenna for 50 MHz. This article describes how to build a J-Pole antenna for the 6-meter amateur radio band. It's a good choice for those who want an antenna with better performance than a simple wire dipole, but at a lower cost than buying a commercial antenna. The project requires soldering copper pipes and some specific materials, but can be built in a day

Build this home made yagi antenna for your 2.4ghz wireless ethernet.

Building details of a VHF colinear antenna with 6 db gain

Constructing a 2.4 GHz high-gain _cantenna_ for wireless networks is detailed, providing a practical approach to extending WiFi range. The author, WB8ERJ, shares insights into building these devices, noting their application in amateur radio for projects like Hinternet or HSMM (High-Speed Multimedia) networks. The article outlines the necessary components and steps, emphasizing the DIY aspect for hams interested in digital modes and local area networking. The resource explains how to determine the correct probe placement within the can, a critical dimension for optimal performance at 2.4 GHz. It references specific measurements, such as the 1.25-inch distance from the can's bottom, derived from calculations for the 2.4 GHz band. This precision ensures the antenna functions effectively for its intended purpose of signal amplification. Readers gain actionable knowledge for fabricating a functional antenna from common materials, suitable for experimentation or practical deployment in a ham shack or field environment. The focus remains on the hands-on construction and the measurable results of improved signal strength.

Sixty-four years of operating experience inform Glynn E. "Buck" Rogers Sr., K4ABT's, insights into the J-Pole antenna, which he describes as a direct descendant of the _Windom_ or _ZEPP_. His first article on the J-Pole appeared in HRC magazine in 1958, and he has since published numerous pieces in publications like CQ Magazine, consistently referring to the J-Pole as a Windom with a folded-back short section forming the parasitic element. He emphasizes that both the Windom and J-Pole are powerful multi-band antennas, performing exceptionally well at harmonics of their fundamental design frequency, and advocates for 50-ohm coaxial cable with a _BALUN_ at the feed-point to avoid RF energy losses. K4ABT details the J-Pole's features, noting its ease of erection, lack of radials, low angle radiation, greater bandwidth, and immunity to terrestrial noise. He highlights its suitability for local nets and distant repeaters, claiming more gain and durability than most ground planes, and its ability to meet stealth antenna requirements. The guide provides specific dimensions for 2-meter (145.000 to 146.000 MHz) and 6-meter (50.500 to 51.500 MHz) J-Pole antennas, including measurements for the long driven element, short tuning stub, and spacing. The construction section illustrates a modified feed technique using an SO-239 chassis-mount coax connector soldered into a copper tee, deviating from the usual hose clamp method. The author also discusses the use of _EMT_ (electrical metallic thin-wall conduit) as an alternative to copper in earlier days. He cautions against building a 75-meter J-Pole due to its impractical length, reinforcing the antenna's optimal application for VHF and UHF bands.

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.

How to build a roofspace antennas and get them to work. Explains how to build an effective antenna in your roof. Very interesting if you don't have possibilities to setup an antenna in your roof.

Presents _Henry Radio Inc._ as a manufacturer of solid-state RF power amplifiers, detailing their capabilities across HF, VHF, and UHF bands. The company designs and builds custom amplifiers tailored for various applications, including amateur radio, commercial broadcasting, military, scientific, and industrial uses. These amplifiers are manufactured in the USA, emphasizing domestic production. Beyond amplifier manufacturing, the resource highlights Henry Radio's role as a distributor for _Bird RF Test Equipment_, including wattmeters, dummy loads, and attenuators. It also mentions _Tohtsu Coaxial Relays_ and a range of miscellaneous amplifier parts and electronic accessories, providing a broader scope of communication equipment offerings. Additionally, the site describes a trunking two-way radio system operating on the 450-476 MHz band, covering significant portions of Los Angeles and Orange County. This service caters to professional dispatch needs for ambulances, taxis, and other commercial entities, requiring no long-term contracts.

Building this antenna is very easy and inexpensive, 6 Foot EH Antenna

Operating a handheld transceiver (HT) while bicycle mobile presents a significant challenge due to the lack of an effective ground plane on a bicycle frame. This project addresses that issue by providing construction details for a 2-meter antenna, specifically adapting the _ARRL Hints and Kinks_ design by Charlie Lofgren, W6JJZ, known as the "Bike 'n Hike Special." The antenna is designed to function efficiently on the 144 MHz band, offering a practical solution for portable VHF communication. The design emphasizes simplicity and portability, crucial for mobile operations where space and weight are at a premium. It details the necessary components and assembly steps, allowing amateurs to build a functional antenna that overcomes the inherent limitations of a bicycle as a radio platform. The original concept was published in the ARRL's well-regarded collection of practical amateur radio solutions. This antenna project enables bicycle mobile operators to achieve improved signal performance compared to a stock HT rubber duck, facilitating more reliable contacts while on the move. It represents a straightforward approach to enhancing VHF communications for active hams who combine cycling with their radio hobby.

Pictures of a multiband dipole, build with simple PVC T and standard electrical wire

How to make the Super antenna. To build this antenna you need a lot that is at least 100 feet across. Antenna covers all bands 80-10 meters + 30, 17, 12 meter WARC Bands This antenna works as a Full Wave Loop on 80 Meters and also works as a 2 wavelength open loop or Bi-Square on the 40 Meter band

Super Morse is the original comprehensive Morse Code training program for the PC. Super Morse permits the user to learn the Morse characters in a very orderly way using several different methods, including one unique to Super Morse; build speed with special exercises

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**.

Excellent guide to build your own G5RV antenna by Lombry

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.

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.

The boomless quad antenna is a unique design that offers versatility for amateur radio operators. This antenna consists of two half-wave dipoles arranged in a square or circular shape, allowing for both vertical and horizontal polarization depending on the feed point. The design facilitates easy installation and rotation, making it suitable for various operating conditions. The construction utilizes strong materials, such as bamboo, and incorporates waterproofing techniques to enhance durability. This project outlines the necessary dimensions and materials, including copper wire and insulators, to successfully build the antenna. It emphasizes the importance of tuning each radiator element for optimal performance. The boomless quad is particularly effective across multiple HF bands, including 14 MHz, 21 MHz, and 28 MHz. By following the detailed instructions, operators can achieve a reliable and efficient antenna setup that enhances their DXing and contesting capabilities.

calculates the dimensions and spacings of the elements needed to build a log periodic antenna, given tao, sigma and the lower and upper cutoff frequencies.

How to easily home-brew baluns even in strange formats 1/1 - 2/1 - 4/1 - 6/1 - 9/1 - 12/1 et 16/1 for bands from 1.8 to 30 (50) MHz in french

Build a double bazooka coaxial dipole, broad-band dipole antenna

PDF file with plans to build an eh antenna for 10 meters band, by lloyd butler VK5BR

Dimensions and plan to build a W5UN EME quagi antenna

Need a general purpose antenna on the magic band? The J-Pole is an easy-to-build and inexpensive device that provides an omni-directional vertically polarised antenna without the need for a ground plane. In technical terms, it is an end fed vertical 1/2 wave which is fed via a 1/4 wave matching stub.

A 9 dB gain 70cm collinear antenna construction is detailed, utilizing eight half-wavelength sections of _RG58/U_ coaxial cable. The design incorporates specific calculations for velocity factor (0.66 for RG58/U) to determine precise element lengths, such as 223mm for a half-wavelength at 444 MHz. A quarter-wave radiating element of #16 solid wire, 169mm long, is added to the top, and a 160mm aluminum tube acts as a quarter-wave counterpoise at the feed point. RF choke baluns, constructed from three _FT50-43_ toroids, are positioned a half-wavelength from the feed point to mitigate common mode current. Assembly involves soldering the coax sections in series, followed by SWR testing during construction and final mounting within a ¾-inch PVC pipe. The article suggests using four half-wave elements for a shorter antenna, noting a potential slight increase in SWR, which can be mitigated with quarter-wave ground radials. The design principles and formulas are scalable for other VHF/UHF bands like 6m, 2m, or 1¼m, providing a versatile homebrew solution for enhanced gain.

Description and phots of a DIY moxon antenna for six meters band, includes clear pictures, drawings and assembling instruction to build this compact antenna for 50 mhz by N2MH

Photos and comments on building an helical antenna for wifi

Documents and schema on how to build a Magnetic Loop Antenna fo 80/30 mtrs

How to Build a Dual-Band Antenna for 2M/70cm presentation PDF file

Build a portable VHF yagi antenna for 2 meters. All you need is two rabbit ear antennas from Radio Shack, two CATV baluns, four feet of 3/4 CPVC pipe with one tee.

Cannot find the inductors you need for an antenna, a tuner or amplifier ? Build your own it is easy!

GM4JMU shortened dipole for 40 meters band. This article illustrates in detail how to build a resonant antenna for 7.030 MHz. Cut two 10.25-meter pieces of insulated wire, wind 40 turns of wire onto plastic tubing, and connect the wire to a central insulator using a choke balun built of RG174AU coax and a ferrite toroid. Once built, the antenna is adjusted by altering the wire length to produce the lowest Standing Wave Ratio (SWR) for best performance. The guide emphasizes careful building and adjustment for the best results.

A custom made 80 meter loop antenna. Reports on usage and tips to build the support.

Build a 2m 8db collinear for portable use

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.

How can you vastly improve your Medium Wave reception? its quite simple really, all you need is 120 foot of wire, a few lengths of timber and an old tuning capacitor with which you can build the answer to every DX'ers prayers, a tuned loop antenna.

Based on HB9CV, F6ITV decribes how build a swiss quand antenna for 28 and 50 Mhz.

Here is a 70cm (440 Mhz) J-Pole antenna that is inexpensive, and easy to build. Author use 1/2 inch copper pipe, and the associated fittings necessary. The dimensions aren't typical however, this is what it took to get its SWR low.

Build your own multiband W3DZZ antenna resonating on 80 40 20 15 and 10 meters band

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.

Optimizing antenna portability for QRP field operations often involves trade-offs between efficiency and physical footprint. The PAC-12 antenna project addresses this by presenting a **multi-band portable vertical** design, specifically tailored for amateur radio operators who travel frequently and utilize compact QRP transceivers like the Elecraft K1/K2 or Yaesu FT-817. This design emphasizes ease of homebrewing using readily available hardware store components, allowing for customizability and repair in the field. The project details the construction of a sectional aluminum rod base, interchangeable loading coils for various HF bands, and a telescoping whip. Key components include 1/4-inch aluminum rod, PVC risers for coil forms, and a BNC feedpoint insulator. The design prioritizes a breakdown length of 12 inches or less, making it highly packable for travel, while still achieving competitive efficiency, as demonstrated by its first-place finish in the HFPack antenna shootout at Pacificon 2001 against a 1/4-wavelength wire vertical. Comprehensive instructions cover whip preparation, **loading coil construction** with specific dimensions for bands from 40m to 10m (with an untested 80m approximation), base section fabrication, and feedpoint insulator assembly. The resource also includes guidance on radial deployment, threading aluminum rod, and showcases various PAC-12 builds by NJQRP Club members, illustrating its adaptability and widespread adoption among QRP enthusiasts.

A well documented plan to build a magnetic loop antenna for Shortwave Listening, includes photos and diagrams.