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Around 17% of the U.S. population experiences some degree of Dyslexia, a condition affecting language processing that can hinder amateur radio license candidates, often leading to repeated exam failures despite diligent study. This resource outlines methods for Volunteer Examiners (VEs) and Elmers to identify and assist candidates with cognitive disorders like Dyslexia and **ADHD**, which affects approximately 4% of U.S. adults. It emphasizes recognizing patterns in missed answers, such as spatial placement errors on answer sheets, and suggests reading questions aloud as an accommodation. The author, NC4FB, shares a structured approach developed over three years, involving extensive candidate interviews and a self-study program. This program utilizes specialized software with keyword highlighting and a unique font to improve comprehension for Dyslexic/ADHD candidates. It also incorporates **MP3 audio files** for subelement questions and correct answers, providing an alternative study method for those who benefit from auditory learning. Key elements of the support strategy include repetition, positive reinforcement, and timely progress updates, often visualized with a color-coded table tracking scores of 85 or higher. The goal is for candidates to pass three consecutive sample exams with at least 85% before attempting the actual license exam, demonstrating mastery of the material.

The PAC-12 Antenna, a multi-band portable vertical, is meticulously detailed in this construction article by James Bennett, _KA5DVS_. The design emphasizes ease of homebrewing using readily available components from local hardware stores, including replaceable loading coils. It outlines the preparation of the 72-inch telescoping whip (originally from Radio Shack, with an alternate source now provided by _Pacific Antenna_), the construction of the loading coils from PVC risers, and the fabrication of the aluminum rod base sections. Specific instructions cover threading aluminum rod with a _1/4-20 threading die_ and assembling the feedpoint insulator with a BNC connector, along with recommendations for radial deployment. KA5DVS, an avid traveler and QRP enthusiast, developed the PAC-12 to address the bulkiness of random wire setups and the limitations of commercial portable antennas like the Outbacker or SuperAntennas MP1. His goal was a lightweight, packable antenna that disassembles into 12-inch sections, achieving an assembled length of approximately 8 feet. The design strategically places the loading coil away from the base for improved efficiency. The PAC-12 notably placed first in efficiency compared to a quarter-wavelength wire vertical at the HFPack antenna shootout during the Pacificon conference in October 2001, demonstrating its practical performance for field operations. Appendix C showcases various _NJQRP Club_ members' PAC-12 constructions, including a 20m beam made with multiple PAC-12 elements.

Hy-Gain TH3jr Tri-band HF 3 Element Beam Covers 10, 15 and 20 Meters assembly instruction manual

The Bazooka antenna, a coaxial dipole, functions as an omnidirectional antenna with vertical or horizontal polarization. Patented in 1939 and refined in 2006, it features a quarter-wavelength coaxial cable with separated conductors. The outer conductor connects to a sleeve, while the inner conductor extends vertically. Initially complex, it has been simplified for versatile use, including military applications. Adding elements can modify its behavior for NVIS or Yagi-Uda configurations. Experiments in 2007 at the Campus de Pesquisas Geofísicas in Paula Freitas-PR demonstrated consistent VHF and UHF performance, showing reliable return loss measurements despite variable weather.

A Lightweight 2m Yagi for SOTA. The boom is 20mm PVC electrical conduit and the elements are 2.4mm aluminium TIG welding rod. The antenna is carried as a single length of conduit with the elements stowed inside the boom, sealing them in with a bung. The driven element is connected directly to 50 Ohm coax with a BN-43-202 balun core to decouple the coax shield.

The longest element has a total length of 14m and has a boom length of 5.5 meters featuring a total bandwith of 166 kHz

Extended Double Zepp measurements for all ham bands, and online calculator. The antenna is constructed much like an ordinary Dipole antenna but with 5/8 Wavelength Elements matched with an added Impedance Matching Section of balanced feed line

This stacking offers a well known simple phasing technique. All elements can be fed in parallel by open wires provided that they are fed in phase. This can be achieved by twisting the open wire phasing-lines at 180 degrees.

Duoband Yagi 2m/70cm with 4 Elements on 2 m and 5 Elements on 70 cm and one Feed point. The 4-El.-Ultralight-Yagi for 2m can be used on 70cm with an SWR of 1,5 without any changes.

A homebrew 13 elements yagi antenna for two meters band. These project includes two model of the same antenna with a 6 and 7 meter boom length. Detailed pictures and nec files are available for download

A project for a 5-over-5 stack on 10 meters

A coaxial cable trap is a fundamental component in multiband antenna design, enabling a single radiator to resonate efficiently on multiple frequencies by electrically shortening or lengthening the antenna element. This project focuses on constructing such a trap for a vertical antenna operating on the 10 MHz (30m) and 14 MHz (20m) amateur bands, providing practical insights into its fabrication and integration. The article outlines the specific dimensions and winding techniques for the coaxial trap, emphasizing the use of readily available materials. It details the physical construction of the vertical element, including the mast and radiating sections, to achieve optimal performance across both target bands. The author shares personal experiences with similar trap designs, noting their effectiveness in previous horizontal dipole configurations. Key construction steps are illustrated with _original photos_, showing the assembly of the trap and its incorporation into the overall antenna structure. The design aims for a compact footprint, making it suitable for limited space installations while still delivering effective DX capabilities on the **30-meter** and **20-meter** bands.

In this article, Steve G0UIH presents a straightforward guide for constructing a lightweight 15m 3 Element Yagi antenna with impressive performance metrics. With a focus on ease of construction and efficiency, the design boasts a nearly 8.2dbi forward gain and 30db front to back ratio. Utilizing readily available materials and a hairpin match for impedance matching, this Yagi offers broad bandwidth and simple tuning for optimal operation across the 15m band.

A Different way to construct a tried and true antenna out of PVC, especially for the 10 meter and higher frequencies.

Integrating a **160-meter vertical wire antenna** with an existing 80-meter Yagi system presents unique challenges for Top Band operation. This project outlines the author's experiences with seasonal antenna removal and reinstallation, a necessary task for agricultural land use. It details specific issues encountered, such as incorrect coil sizing and relay configuration problems, providing practical insights into common pitfalls. The article describes the iterative tuning process, comparing **NEC model** predictions with actual on-air performance. It emphasizes the importance of precise measurements and adjustments to achieve optimal resonance and impedance matching. The author shares lessons learned from troubleshooting, including the impact of ground system integrity and feedline considerations. Concluding with an antenna checkup, the resource addresses long-term maintenance aspects, including galvanic corrosion prevention and general upkeep for reliable operation.

Learn about the practical design and construction of Yagi antennas for ham radio operators. This post explores the benefits of Yagi antennas in receiving and transmitting RF signals, concentrating signal energy in one direction for long-distance communication. Discover the theory behind Yagi antennae, the importance of element size and spacing, and the resources available for sizing and construction. Whether you're interested in OTA television or amateur radio communication, understanding Yagi antenna design can enhance your signal reception and transmission capabilities.

Online antenna parts store, providing many accessories for amateur radio antenna homebrewing. Boom joiners, aluminium parts, elements clamps, filters, ferrites, fasteners, plasti caps, dipole elements. Based in UL

a 20M quarter-wave vertical antenna with a 6m telescopic mast, 1:1 balun, and spiral-wound driven element. Designed for QRP at 14.285 MHz, the antenna’s performance exceeded expectations, delivering low SWR and surprisingly quiet reception. Initial testing yielded successful contacts with European stations and EC1KR, showcasing its effectiveness. Compact and easy to deploy, the antenna promises to be an excellent portable solution for future hilltop operations.

The **Nilex Morse Tutor** is an HTML5 web application designed to teach Morse code reception, adapting to user proficiency by adding new characters as readiness is detected. It prioritizes practice on less familiar letters, numbers, symbols, words, and phrases, while minimizing repetition of already mastered elements. The program offers multiple learning orders, including "Q7ZG..." (Ward/Jim's), "KMRS..." (PU5EPX/Koch), "KMUR..." (lcwo.net), "AENT..." (CWops CW Academy), "TEAN..." (Stephen C Phillips), "ANET..." (Vic VE3YT), and "ETI5..." (Ham Whisperer), alongside an alphabetical option. Users can customize the learning experience by enabling or disabling automatic progression, and selecting specific content categories such as numbers, symbols, words, phrases, QSO bits, Ham Radio Bands, X+Y=Z math, and units. Audio settings are adjustable for volume, speed (WPM), tone frequency, and keyshape/keying envelope, allowing for a personalized auditory environment. The interface provides visual feedback with blue bars indicating practice emphasis and gray bars for reserved characters, with clickable bars for manual character selection. Developed by "Nosey" Nick Waterman, VA3NNW, this tutor is based on earlier versions by Jim Wilson and a 1977 QST article. A significant October 2019 rewrite incorporated a new WebAudio sound library by AwesomeAidenW, improving offline functionality and mobile support. The content library was expanded to include 3000 top Google words, 2284+ General Service List words, ISO country codes, capital cities, US states, Canadian provinces, UK counties, common names, periodic table elements, quotes, Q-codes, electronic components, ham abbreviations, and example call signs. The software is distributed under the GNU GPL V2 license.

This project involves constructing a dual-band Moxon antenna, optimized for ham radio enthusiasts, with functionality on both the 10-meter and 6-meter bands. The antenna is designed to operate using a single 50-ohm feedpoint, acting as a mini-beam on 28 MHz (10 meters) and as a 2-element Yagi on 50 MHz (6 meters). Performance-wise, it offers a 4.0 dBd gain on 10 meters and 4.3 dBd on 6 meters, with impressive front-to-back ratios of 30 dB and 11 dB, respectively. Builders like Aleks (S54S) and Marcio (PY2OK) have successfully brought this design to life using the provided specifications. Aleks noted that bending the corners of the structure proved especially useful during assembly. The project comes with a detailed parts list, highlighting the use of aluminum tubes with different diameters and lengths to form essential components like the reflectors and radiators. For those looking to fine-tune the antenna, adjustments can be made by altering the length of certain parts that fit into larger tubes. The feeding system is equipped with a balun to accommodate different power levels, making the design versatile enough to handle outputs of either 300 watts or 1 kilowatt.

KlaTrack is a Windows-based software application designed to assist amateur radio operators with satellite communication by predicting spacecraft visibility. It provides a simple interface to determine when specific satellites will be above the local horizon, a critical factor for successful two-way contacts via amateur radio satellites. The program processes _Two-Line Element_ (TLE) data to calculate orbital mechanics, offering a practical tool for satellite operators to plan their operating windows. It supports real-time tracking and displays essential pass information. This utility simplifies the complex task of satellite tracking, allowing operators to focus on making contacts rather than manual orbital calculations. While specific gain figures or distances are not quantified, the software's core function directly supports achieving successful satellite QSOs by providing precise pass predictions. It is particularly useful for operators engaging in activities like working the International Space Station (ISS) or other low-Earth orbit (LEO) satellites, where short pass times and precise timing are crucial for maximizing contact opportunities.

A 14.12 dBi gain three elements cubical quad antenna for the six meters band. This Quad Antenna design page include a MMA model available to download and dimensions for each element.

A growing set of pages with tools and analyses of various elements of data elements based on Sherwood RX tests

In this article the author describes his personal experience on some antennas for 50 MHz he tested on the field, the six meter Dipole, Vertical, Moxon, a 3 element Yagi and an Omniangle antenna.

This is a design based on the QuickYagi 4 software by WA7RAI with some changes for practical reasons. The beam uses 6.5 metres of standard 25mm square boom, 12mm diameter elements without tapers. The actual boom length used is 6.3 metres and all parts are readily available.

Constructing a 5-element quad antenna, the author aimed for low cost and simplicity, resulting in an effective design with 11 dBi gain and SWR of 2:1 or better across the 2-meter band. Using wood and dowels, the antenna costs under $8 and takes less than two hours to build with basic tools. The model predicts excellent performance, confirmed by ARRL Lab measurements. Practical field results demonstrate improved communication, even in simplex mode.

This six element LFA Yagi for six meters has a 1.5 inch square boom with a 1.5 inch secondary boom beneath the first. This ensures the 7.3 metre long boom will not sag and will not require any guying. This antenna has 12.3 dBi Gain and just over 23dB F/B.

This design makes the most of having to put an aerial in the attic. This inverted-vee yagi is giving good results at GW0GHF. Directive gain is about 6 dBd. The front-to-back ratio is not brilliant, about 20 dBd.

Build your own 3-IC Iambic Electronic Keyer. Here, you will find schematics and operation descriptions. Includes Dot/Dash Memory, Progressive Element Weighting

The author wants a compact, switchable antenna for 40-meter ham radio. They compare 3 designs: rectangle, short-tipped W6NL, and T-hat. All work well electrically, but mechanics matter for a large antenna. The rectangle needs strong support, while the T-hat is sturdier with slightly longer elements. The T-hat design wins for now, but the author will focus on its mechanical details next.

Online antenna calculator for a basic 3 elements yagi uda directional antenna. The described antenna design offers a front-to-back ratio of at least 20 dB, a gain exceeding 7.3 dBi, and a bandwidth (SWR < 2) of approximately 7% around the center frequency. It has an input impedance of 50 ohms when using a straight split dipole, which can be substituted with a folded dipole of the same length, increasing the impedance to 200 ohms. A matching balun is required for coaxial feeder connection, and the boom should be made of a dielectric material, like wood.

The article describes the construction of a Lindenblad antenna, which is well-suited for receiving signals from low-orbiting weather satellites. The key points are: The Lindenblad antenna has an omnidirectional horizontal radiation pattern and is optimized for low to medium elevation angles, making it ideal for tracking passing satellites near the horizon. It is designed to receive circular polarization, which is common for weather satellite signals. The antenna is constructed using 4 folded dipole elements arranged on a cross-shaped frame. The necessary materials include a plastic junction box, PVC tubing, and aluminum rods to form the dipole elements. The article provides detailed instructions for preparing the components, assembling the dipoles, and connecting the feed lines to create the complete antenna. The completed antenna can be mounted on a vertical support, with the dipole elements angled at 30 degrees from horizontal, to optimize reception of the passing satellites. The author notes that the design was originally published in a now-defunct magazine, Meteo Satellite Inf", in 1993

This DIY guide details constructing a 5-element Yagi antenna for VHF frequencies. Yagi antennas offer directional signal transmission/reception compared to omnidirectional ones. The guide covers material selection (aluminum, screws, etc.), design using software or formulas, and step-by-step assembly including cutting elements, drilling holes, and attaching the coaxial cable. While calculations are provided for a 146 MHz design, adjustments are necessary for different frequencies. Safety precautions and potential result variations are emphasized.

A 4 element Yagi Antenna for six meters band

Learn how to build wire Yagi antennas for your ham radio setup. Discover how smaller wire elements can offer practical and portable options for temporary operations. Explore designs like the Hex Beam, Spider Beam, and Moxon that require less mechanical complexity and can be easily rotated or supported. Find out how to construct and hang wire Yagis from ropes, trees, or masts with inverted vees or horizontal elements. Get tips on element positioning, gain, and beamwidth considerations. Follow simple construction steps using a rope boom and marking element positions for efficient assembly. Enhance your ham radio experience with versatile wire Yagi antennas.

Presents a detailed construction guide for a 9 dB, 70cm collinear antenna, utilizing readily available _RG58/U_ coaxial cable and PVC pipe for housing. The resource outlines the critical calculations for ½ wavelength sections at 444 MHz, incorporating the coaxial cable's velocity factor of 0.66, which yields a section length of 223 millimeters. It specifies the preparation and soldering of eight such half-wavelength sections, each cut to 231mm to allow for trimming, forming the core of the array. Further instructions detail the integration of a ¼ wave element (169mm #16 solid wire) at the top and a ¼ wave aluminum tube (160mm, 5/16 inch) at the bottom, crimped to the feed point's braid. The guide also addresses RF common mode current suppression by suggesting the use of _FT50-43_ toroids on the feedline. Final assembly steps cover mounting the antenna within ¾" PVC pipe using a wooden dowel, waterproofing connections, and initial SWR checks. The article also discusses scaling the design for different element counts and other VHF/UHF bands.

This project introduces the Loggi, a hybrid antenna merging the wide frequency coverage of log-periodic dipole arrays (LPDA) with the high gain and front-to-back ratio (F/B) of Yagi antennas. Traditional LPDAs span broad frequencies with moderate gain and low VSWR, while Yagis provide high gain and F/B over narrow bands. By analyzing high-Tau LPDA designs, it was found they could nearly match the gain of VHF/UHF Yagis while maintaining excellent patterns, F/B, and front-to-rear ratios (F/R). Optimizing specific elements for target frequencies (e.g., 144.1 MHz) led to the Loggi, which uniquely features all driven elements without passive directors or reflectors. This design effectively functions as a narrowband optimized LPDA, with front elements acting like Yagi directors and rear elements like Yagi reflectors, thus enhancing gain and directional characteristics while retaining broad frequency versatility.

For amateur radio operators engaging in portable operations like SOTA or POTA, rapid deployment of an effective antenna system is paramount. This video resource details the assembly process for the Buddipole multiband dipole antenna, showcasing its components and how they fit together. Rob, VK5SW, systematically presents the mast, coil arms, radiating elements, and the VersaTee hub, emphasizing the modular design that allows for quick configuration changes across various HF bands. The demonstration highlights the antenna's adaptability for different operating environments, from a ground-mounted vertical to a horizontal dipole. The video illustrates the ease with which the antenna can be packed and deployed, making it a practical choice for activations where setup time is limited. The Buddipole's design facilitates efficient band changes and tuning, crucial for maximizing QSO opportunities during field operations.

This page provides information on designing a lightweight Moxon antenna for the upper HF bands and VHF. The Moxon antenna is a compact version of a 2-element Yagi with folded elements, offering good forward gain and a high front-to-back ratio. It is designed for a single band with a feed-point impedance close to 50 ohms. Hams can orient the antenna horizontally or vertically, with polarization following the configuration, affecting radiation patterns. The page allows users to generate radiation pattern plots, VSWR charts, antenna currents diagrams, and Smith charts for their antennas on different ground types, helping them understand antenna performance in the field.

A home made project for a 7 element yagi antenna for the two meters band based on the DK7ZB original desing.

The article describes a high-gain, compact beam antenna design for the 2-meter band (144-146 MHz). The NSH 4x4 Boomer is a 4-element antenna that is mounted on a 4-foot boom with an 8.2 dB gain, 1.2:1 SWR, and a front-to-back ratio of 18 db. It is designed for mobile operations and little area, making it perfect for field usage such as disaster management. The design employs regularly spaced parts with a straightforward gamma match for tuning, and the construction materials include a square boom and polished aluminum tubes. In local and portable tests, the antenna worked regularly, achieving contact distances of up to 15 kilometers.

Method, Units of Measure, and the Dipole Standard of Reference. This article helps in understanding where does beam gain come from in directional aerials like in example Yagi antennas.

This page provides construction details for a 4-element 10-meter Yagi antenna with 28 Ohm impedance. It includes information on the elements, positions, diagrams, and data related to frequency, gain, front-to-rear ratio, radiation resistance, SWR, and loss. The content is aimed at hams or radio operators interested in building and optimizing Yagi antennas for the 10-meter band.

The author describes his experience building and using a Beverage antenna for the 40-meter band. Despite encountering some challenges, the antenna offered some improvements in receiving stations compared to a 3-element inverted Vee antenna. The Beverage antenna showed a significant daytime signal-to-noise ratio improvement and received signals better than the Vee antenna. However, the front-to-back ratio was not ideal, and the transmit power seemed to affect the Beverage antenna. Overall, the author concludes that the Beverage antenna might be more suitable for locations with higher noise levels. The total cost of the antenna was around 30 Euros.

The PA0FRI Unbalanced/Balanced ATU is a home-built antenna tuner designed to efficiently match a W8JK 2-element beam antenna fed with a 450-ohm twin lead. Based on PA0FRI’s S-Match design, it optimizes energy transfer while maintaining balance, reducing losses, and ensuring proper radiation. The tuner uses a roller inductor, air variable capacitors, and a T200 iron powder coil, allowing fine-tuning across 14-50 MHz. Extensive lab tests confirm minimal attenuation and precise impedance matching, making it a reliable and efficient ATU for balanced antennas.

This is a plan for an optimized element UHF Yagi Antenna for UHF Bands featuring a 9dBd forward gain, a 13 dB front-back ratio, and a bandwith of 10 MHz on the 430-440MHz range.

Phased array antennas are composed of multiple individual antenna elements that can have their phase and amplitude controlled to steer the main beam direction in real-time. They are used in radar, communications, and electronic warfare, and offer improved gain and reduced side lobes. A comprehensive document on Phased Arrays include techniques to increase the Antenna Gain and change the Radiation Pattern

The Butternut HF2V, originally a two-band vertical antenna for 80m and 40m, was enhanced by the user to include 30m and 20m bands for better digimode DX work during the solar minimum. The additions used components adapted from the HF6V and innovative methods for the 20m addition, either through a parallel vertical element or a lower-mounted independent element, minimizing band interaction. This modified four-band antenna now supports high power across popular HF bands using a single feedpoint.

Many low-power SSB rigs and kits lack dedicated speech processor circuitry, although most modern HF rigs include it. Speech processing is crucial for low-power SSB to overcome QRM. This simple, low-cost circuit integrates a microphone element and can be housed in a defunct desk mike. It features a feedback amplifier, audio preamplifier, and adjustable speech compression control

This article provides a cost-effective and reliable method for fixing antenna elements in the traverse of HF/UHF Uda-Yaga antennas. It outlines a step-by-step process using soft galvanized steel wire, eliminating the need for special adapters or additional holes. The method described ensures a secure attachment without compromising the mechanical strength of the traverse, offering a durable solution for ham radio operators constructing antennas. The use of galvanized steel wire guarantees long-lasting stability, making it a practical and efficient technique for antenna assembly.