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Query: 4 meter antenna
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- Antennas > 20M > 20 meter Dipole Antennas
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- Antennas > 40M > 40 meter Dipole Antennas
- Antennas > 40M > 40 meter Loop Antennas
- Antennas > 40M > 40 meter Magnetic Loop Antennas
- Antennas > 40M > 40 meter Vertical Antennas
- Antennas > 6M > 6 meter J-Pole Antenna
- Antennas > 6M > 6 meter Yagi Antennas
- Antennas > 40M > 40 meter Delta Loop Antennas
- Antennas > 40M > 40 meter Yagi Antennas
- Antennas > 6M > 6 meter Moxon Antennas
- Manufacturers > Wattmeters
- Antennas > 10M
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- Technical Reference > Arduino
- Radio Equipment > HF Vertical Antenna > Cushcraft R8
- Antennas > Halo
- Radio Equipment > HF YAGI Antennas > Hy-Gain TH3JR
- Antennas > Morgain
- Manufacturers > Test Equipment
- Technical Reference > Test Equipment
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NA4RR manufacture a six band hexagonal beam antenna for ham radio, covering 6, 10, 12, 15, 17, and 20 meter.
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Learn how to easily build a 10-meter vertical antenna, perfect for DX contacts on the amateur radio bands. This flowerpot or T2LT design is portable, efficient, and ideal for ham radio operators looking to improve their DX performance. With just a few basic tools and materials, you can construct this antenna for portable operations or as a home station setup. Discover how to set up the antenna, improve its performance by raising it higher, and start making contacts with stations around the world. Watch a step-by-step guide on YouTube for building and testing this DIY ham radio antenna.
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A j-pole antenna plan with drawings and dimensions that can help you on building your own j-pole antenna for the six meters band
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Listen to HF communications via the KiwiSDR online receiver located in Badgad IRAQ locator LM23fh. This web receiver is running a MLA 30+ antenna and can be tuned easily on all HF bands from 10 to 80 meters.
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A simple superheterodyne receiver (3.5–30 MHz) for amateur radio achieves stable SSB-CW reception using modern BJTs, an AD831 mixer, a 6-pole quartz filter, and Seiler oscillators. Designed with high IF (4.5 MHz), compact AM-FM variable capacitors, and modular resonant circuits, it ensures selectivity, image rejection, and stable tuning. Built in a copper-lined wooden case, it features practical assembly techniques but lacks advanced features like AGC or S-meter. Effective on basic antennas, it achieves global reception.
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Building an End-Fed Half-Wave (EFHW) antenna from a kit, as detailed by Frank Bontenbal, PA2DKW, with process photos by Bob Inderbitzen, NQ1R, offers a practical approach for hams. This specific kit, a collaboration between ARRL and HF Kits, targets 10, 15, 20, and 40 meters, making it a versatile option for HF operations. Unlike a center-fed dipole, the EFHW is a half-wavelength antenna fed at one end, which simplifies deployment, particularly for portable use. The construction guide meticulously outlines the assembly of the 49:1 impedance matching network, crucial for transforming the antenna's high impedance (around 2,500 Ohms) to a transceiver-friendly 50 Ohms. Steps include preparing the enclosure by drilling holes for the coaxial connector and antenna connections, followed by the precise winding of enameled copper wire onto a toroid to create the transformer. The guide emphasizes careful insulation removal and soldering for reliable connections. Final assembly involves integrating a 100 pF capacitor for higher band compensation, soldering the transformer's primary and secondary sides, and conducting SWR tests with a 2K7 resistor or a half-wavelength wire. The document also provides examples of wire lengths for different bands, such as 16 feet for 10 meters or 66 feet for 40 meters, demonstrating the transformer's adaptability for various half-wavelength configurations.
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Experimentin wire antennas on top band using several type of aerials. This includes a 40 to 160 meters EndFed Half Wave kite antennas and 160m/80m loaded vertical antenna.
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Operating marine mobile with antennas for 15-17-20 meters band.
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This article explores the evolution of antenna choices for DXpeditions, focusing on the shift from mono-band VDAs to a multi-band solution. It details the design and construction of a lightweight, versatile 20-17-15m VDA, utilizing readily available materials like fishing rods and IKEA breadboards. The author discusses challenges, adjustments, and offers guidance for replication.
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This article provides details on building a 6 Meter J-Pole antenna using PVC pipe for an enclosure.
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This article documents the author's journey in building, modifying, and testing a DIY short vertical antenna for 40, 30, and 20 meters, with potential 80m capability. Initially inspired by Parks On The Air (POTA), the author explores pedestrian mobile operation and details various experiments to enhance antenna performance. The piece highlights challenges, SWR tuning, portability, and practical results, emphasizing a balance between efficiency and size. Ultimately, it showcases the adaptability of DIY antennas for portable ham radio applications.
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Bring the six meters with you during your hoilidays. This article features a portable moxon antenna for 50 MHz used for sota portable operatios
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This antenna looks like an inverted L antenna, yet it is not, it could also be viewed as a 160m off-center fed dipole antenna, it looks more like an end-fed 1/4 wave 160 meter antenna.
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The _G3TSO_ Mobile Antenna Page details construction and tuning methods for mobile antennas operating across **10 to 160 metres**. The content describes a Hustler-based design, optimized for RF performance and vehicle speeds, featuring centre loading. For optimal operation on various bands, the loading coil placement requires clearance from the vehicle body. Antenna resonance is critical for efficient mobile operation. A mobile antenna's base impedance may be as low as 27 ohms, requiring specific matching to achieve maximum radiation, as a minimum SWR at the transmitter does not always indicate resonance or maximum output. Tuning involves physical adjustment of antenna length to achieve resonance at the operating frequency. The _G3TSO_ page outlines a tuning procedure utilizing a low-power signal source and a field strength meter to identify maximum radiation before impedance matching. Loading coil placement, either at the base, center, or top of the antenna, influences radiation efficiency and mechanical stability for mobile installations. Centre-loaded whips, such as the Hustler design, offer a compromise between efficiency and stability, often for single-band operation. Helically wound antennas, including those for **28 MHz**, may present base impedances around 17 ohms, resulting in a 3:1 SWR at resonance. Low resistance grounding at the antenna base is also specified for optimizing performance and minimizing RFI during mobile operation. DXZone Focus: Mobile | Any | Antenna Tuning | HF
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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
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Learn how to easily improve your handheld VHF performance on the 2-meter band with the Flowerpot antenna. This simple DIY antenna made from coaxial cable requires minimal tools and materials, providing a big range upgrade compared to standard rubber-duck antennas. Discover how to build, tune, and optimize the Flowerpot antenna for excellent performance. Ideal for hams looking for lightweight, portable solutions for handhelds, mobile rigs, home stations, SOTA/POTA activations, and emergency communication.
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Explains the fundamental purpose of a repeater, detailing how these automated relay stations overcome distance and terrain limitations for VHF/UHF communications. It traces the historical development from early Bell Telephone Labs "relay" stations in 1922 to Art Gentry, W6MEP's, pioneering K6MYK amateur radio repeater in the mid-1950s, which remains active today. The resource clarifies the distinction between simplex and duplex operation, including the unique function of a "parrot repeater" for single-frequency recording and playback. Delving into the internal workings, the guide breaks down a repeater into its core components: the antenna system, feedline (often _Heliax_ or hardline for minimal loss), duplexer, receiver, transmitter, and controller. It emphasizes the critical role of the duplexer in preventing receiver desensitization by isolating transmit and receive signals, even with distinct frequencies. The discussion highlights the importance of high-performance, durable antennas and low-loss feedlines, citing examples of equipment installed in the 1960s and 1970s that are still in perfect working order. Operating a repeater is also covered, with an explanation of frequency offset (e.g., the 600 kHz standard for 2 meters) and the function of _CTCSS_ (PL tone) for access. It outlines standard input/output offsets for various bands, from 6 meters to 23 centimeters, while noting regional variations. The guide also touches on features like autopatch and Digital Voice Recorders (DVRs), providing a solid foundation for understanding repeater technology and usage.
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Paul McMahon presents a compact VSWR meter designed for QRP portable use, ideal for SOTA operations with rigs like the FT817. The device, constructed from readily available components, employs a simple resistive bridge for wideband performance from 1.8MHz to 52MHz, with diminishing accuracy at higher frequencies. Key features include no need for external power, simple calibration, and operation with low power levels. The design, detailed with parts lists, schematics, and construction guidelines, ensures a 2:1 worst-case VSWR to protect transceivers during antenna matching. Calibration points are set for accurate VSWR readings at various loads.
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The antenna I built was inspired by a portable delta loop designed by Doug DeMaw, W1FB. Given that I constrained myself to a 50-foot roll of speak wire, I scaled my antenna for the 20M band. Using the formula, 1005 divided by the frequency in megahertz, I calculated a total length of 71 feet (21.6 meters) for the center of the 20M band.
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A portable loop antenna, made with a 3 meter loop resonates with the chosen capacitor from just below 7MHz to about 28.300MHz which makes it usable on the bands from 40m to 10m.
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This document provides a detailed guide on constructing and mounting a folded dipol for the 146 MHz frequency in a vertical configuration to be used in Yagi antennas. The step-by-step instructions and diagrams included make it easy for hams to build and set up this type of antenna. Understanding and implementing this design can enhance the performance of radio communication for Amateurs operating in the 2-meter band. Whether you are looking to improve your signal strength or experiment with antenna designs, this resource offers valuable insights and practical information.
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The 80-meter Skyloop antenna, a top-performing HF antenna, excels in weak signal work, low-noise operation, and omnidirectional coverage. Ideal for fixed stations, it delivers strong performance at low power, outperforming many alternatives, including 80m half-wave end-fed antennas. Requiring significant space for deployment, it’s well-suited for NVIS and groundwave use. Though not portable, it’s cost-effective and durable, with minor maintenance needs. Tuning may require adjustments for optimal resonance. It’s a standout for base stations, though a lighter portable version could enhance its versatility.
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Reflected power and VSWR Metering on Yaesu FT-817, and proper interpretation of real values. The power output meter it is a relative indicator of the antenna match that the radio is experiencing. Reference table and how correctly read the values of the Yaesu internal meter.
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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.
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Mad your own simple FS meter. It is the simplest thing to make and is good enough to see if the antenna under test is radiating more power than your old ground plane, old mobile vertical or just radiating at all in a particular direction or in all directions.
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A Different way to construct a tried and true antenna out of PVC, especially for the 10 meter and higher frequencies.
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This blog chronicles the development of an 80-meter vertical antenna for amateur radio operation. The author constructs a top-loaded vertical using fiberglass poles, achieving significant performance improvements over their previous end-fed wire antenna. Comparative testing using the Reverse Beacon Network and on-air contacts demonstrates 8-10 dB gain on the east coast. The project evolved to include 40-meter capability through a modified design featuring a four-wire vertical cage, loading coil, and strategic guying system. Despite challenges with signal wobble during windy conditions, the vertical consistently outperforms the end-fed wire, particularly for reaching distant stations during nighttime propagation.
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The DK7ZB-Dualband-Moxon-Beam provides a compact, high-performance antenna solution for 28 MHz and 50 MHz operations, utilizing a single 50-ohm feedpoint. This design functions as a mini-beam on 10 meters, achieving a gain of **4.0 dBd** with a front-to-back ratio of _30 dB_, while operating as a 2-element Yagi on 6 meters, yielding a gain of **4.3 dBd** and an 11 dB F/B ratio. The antenna's dimensions are approximately two-thirds that of a full-size 10-meter beam, making it suitable for smaller spaces. Construction details include a parts list specifying aluminum tubes of various diameters and lengths for the reflector and radiator elements. Builders like Aleks (S54S) and Marcio (PY2OK) have successfully replicated the design, with Aleks noting the utility of bending corners during assembly. Fine-tuning is accomplished by adjusting the length of specific elements that slide into larger tubes. The feeding system incorporates a balun, with options for either 300 watts using RG188 on an FT140-43 core or 1 kilowatt using _Aircell-5_ on an FT240-43 core, ensuring versatility for different power levels.
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Learn how to design and analyze a folded trifilar antenna for the 80-meter band. Based on a description from RAF antennas between 1940 and 1970, this article provides step-by-step guidance on modeling the antenna, calculating resonance frequency, adjusting dimensions, and verifying performance. Perfect for hams looking to improve their antenna setup for better transmission and reception on the 80M band.
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This antenna works on 17, 20, and 30 meters, with the best bandwidth on 20 meters. The bandwidth on 17 and 30 is quite small but usable. There is a 20 KHz bandwidth on 20 meters.
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Magnetic loop receive antennas manufacturer. W6LVP loops cover 2200 through 10 meters (135 kHz through 30 MHz) with no tuning or adjustment.
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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.
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Build A Shortened 40 Meter Vertical antenna For POTA / SOTA Activations. A project for a portable wire antenna for 40 meters band suitable for POTA or SOTA operations.
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This document details the construction of a multi-band end-fed antenna, suitable for situations with limited space for larger antennas. The design utilizes a 1:49 to 1:60 impedance transformer to match a half-wave wire antenna fed at one end. Compared to a traditional dipole, this antenna resembles a highly unbalanced Windom antenna with one very long leg and a virtual short leg. The design eliminates the need for radials but relies on the coax cable shield for grounding. The document recommends using at least 10 meters of coax and installing a common mode filter at the entry point to the shack for improved performance.
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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.
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This antenna is designed for 40, 80 and 160 meters to complement a tri-band beam normally taken on DX peditions for 10, 15 and 20 meters, so six bands can be worked with only two antennas.
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144MHz 2m Portable Yagi VHF Beam Antenna. This page contains construction details on a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.
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Steve Nichols, G0KYA, presents a practical examination of ground systems for vertical antennas, drawing heavily on the empirical research of Rudy Severns, N6LF. He explains that a robust radial field is crucial for ground-dependent verticals, effectively replacing the antenna's "missing half" and mitigating severe RF absorption in lossy soil. Nichols clarifies that surface radials do not strictly require a quarter-wavelength; instead, deploying a minimum of 16 to 32 shorter wires often yields superior results compared to fewer, longer ones. The presentation also addresses the common SWR paradox: a poor ground might show a perfect 1:1 match, but adding radials, while potentially raising the SWR to around 1.4:1, significantly improves true radiation efficiency. Nichols defines counterpoises as elevated wire networks that substitute for earth connections, offering solutions for limited-space installations, such as the **Folded Counterpoise (FCP)** for 160 meters. This resource provides actionable engineering data for optimizing vertical antenna performance.
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Original HF magnetic loop antenna designed by the author to work in conjunction with QRP transceivers like the FT-817 in portable operations. In this configuration the loop can operate from 30 to 10 meters. Using a two spires radiator of the same diameter it also covers 40 meters.
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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.
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A small magnetic loop antenna, often employed by hams facing antenna restrictions or high local RFI, offers a compact solution for HF operation. This resource details the construction of a foldable magnetic loop designed for the 40m through 17m bands, emphasizing its high-Q factor and _Faraday coupling_ for effective noise rejection and narrow-band filtering. The guide outlines material selection, advocating for copper over aluminum to maximize efficiency, and provides insights into the physics governing its operation, including impedance matching and resonance principles. Practical application of this antenna design is particularly beneficial for QRP enthusiasts and portable operators seeking a stealthy, high-performance antenna. The construction process includes specific details for a 1-meter diameter loop, a 140pF variable capacitor, and a _gamma match_ for impedance transformation. Performance comparisons suggest that while a full-size dipole might offer slightly better gain, the magnetic loop's ability to mitigate local noise often results in a superior signal-to-noise ratio, making it a viable option for challenging RF environments.
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WB8LZR details the construction and initial field results of a multi-band vertical wire antenna, designed to complement his existing horizontal loop for improved DX on 80 meters. The antenna utilizes a 67-foot vertical wire, configured as a quarter-wave radiator on 80m, and employs a 1:1 current balun for RF isolation on 80m, 30m, and 17m. For bands like 40m, 20m, and 10m, where the wire acts as a half-wave or full-wave radiator, an additional impedance transforming _unun_ is integrated to manage the significantly higher feedpoint impedance and voltage. The author notes the vertical's performance as a receiving antenna, observing reduced noise compared to his main horizontal loop, particularly on 80m, and even hearing some long-path signals the loop missed. Initial QRP contacts, including a **1-watt** QSO with a _VP2 station_ on 30m, demonstrate its transmit capability. While the radial system is currently rudimentary, the project outlines practical considerations for multi-band vertical deployment and impedance matching.
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A rotatable 40-meter dipole antenna designed and constructed to fit within backyard constraints. The project utilized two fishing poles attached to a fiberglass center pole, resulting in an easy-to-build, lightweight, and cost-effective antenna. Essential materials included fishing rods, a center support pole, mast support, and basic tools. Linear loading was implemented to achieve the necessary length for optimal performance. The antenna, which proved effective during the contest, is ideal for field days and additional contest bands. Assembly and installation were straightforward, showcasing the antenna's practicality and efficiency.
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This article describes the phases for the construction of a Yagi antenna. The calculations of the parameters are made using 4NEC2 software. This type of antenna is used for transmissions and receptions of electromagnetic waves. The project shown here refers to the frequency of 433.92 MHz.
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An homebrew HF Magnetic loop made with 2m length of 6mm diameter copper pipe formed into a near circle as the low loss inductor, a short length of coax as a capacitor,a short length of mains cable, again as a fixed tuned capacitor, a tunable 365pF air spaced capacitor, and a small Jackson C804 airspaced variable with a small 3-35pF trimmer in parallel
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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.
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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.
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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.
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When building antennas for the Wifi band (Like the 8dBi omni), a need for an easy way to check the antennas arose. A Voltage Standing Wave Ratio (VSWR) meter useable at the 2.4GHz band is however, hard to find.
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Four distinct amateur radio bands, specifically 40, 30, 20, and 15 meters, are addressed by a portable dipole antenna design. This antenna utilizes a manual switching mechanism, employing "fast-on" or flying connectors to change bands. The design is presented with an animated plan, illustrating how operators can adjust the operating frequency by opening and closing specific connections on the antenna elements. The resource describes a _4 savos dipol_ (4-band dipole) that can be shortened for specific band operation. It provides practical information for hams seeking to construct a versatile, multi-band wire antenna for portable operations or fixed station use. This design offers a straightforward approach to achieving multi-band HF capability without complex tuning units, making it suitable for field deployments like SOTA or POTA activations where rapid band changes are beneficial.