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Query: 40m 20m antenna
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GAP Titan DX Evaluation, antenna for 10m 15m 20m 40m 80m
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This multiband wire antenna it is an off centre fed dipole, with 10 feet of vertical radiator, needs no tuner on 40m, 20m and 10m and works fine on all bands above 40m with a tuner, and even below 40m on 60m, and 80m.
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Multiband Center-Loaded Off-Center-Fed Dipole (CL-OCFD) antenna that work on 80m 40m 30m 20m 15m 10m. The Center-Loaded Off-Center-Fed Dipole (CL-OCFD) antenna, developed by Serge Stroobandt, offers a versatile solution for amateur radio enthusiasts, covering multiple HF bands (80, 40, 30, 20, 15, and 10 meters) without the need for an antenna tuner. This innovative design utilizes a capacitor for resonance on the 80-meter band and a resistor to manage static charges. The CL-OCFD enhances bandwidth and simplifies operation, making it a significant advancement on OCF Dipole design.
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Demonstrates the construction and performance of an updated ZS6BKW multiband dipole, a variant of the _G5RV_ antenna, specifically designed for HF operation. The article details a real-world installation using 13.5m copper wire elements and 12.2m of 450 Ohm ladder line, configured as a sloping inverted-V with the apex at 10m and ends at 4m above ground. It covers the critical aspect of impedance matching, incorporating an 8-turn choke balun at the feedline transition to RG-58U coax to mitigate RF common mode current. Measurements confirm favorable SWR readings below **1.3:1** on 7.1 MHz, 14.11 MHz, 18.06 MHz, and 24.8 MHz, indicating effective resonance across 40m, 20m, 17m, and 12m bands. The installation also shows usable SWR dips on 3.55 MHz (5:1), 29.02 MHz (2:1), and 50.84 MHz (3:1), extending its utility to 80m, 10m, and 6m with an antenna tuning unit. Initial on-air results report clear reception of stations over **5000km** away, validating its DX potential.
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The ZS6BKW multiband HF antenna, a design by ZS6BKW (G0GSF), functions effectively on multiple HF bands without requiring an Antenna Tuning Unit (ATU) for 40, 20, 17, 12, 10, and 6 meters. This antenna, approximately **27.51 meters** (90 feet) long with a 12.2-meter (40-foot) open-wire feeder, is a direct descendant of the _G5RV_ but offers superior multi-band resonance. It can be deployed as a horizontal dipole or an inverted-vee, with the latter requiring only a single support and maintaining an apex angle of at least 90 degrees to prevent signal cancellation. Performance data, recorded with an MFJ Antenna Analyser, indicates SWR values of 1:1 on 7.00 MHz (40m) and 14.06 MHz (20m), with SWR below 1.3:1 on 17m, 10m, and 6m. While primarily designed for these bands, the antenna can be adapted for 80m, 30m, and 15m with an ATU, preferably at the balanced feeder's base. The use of 450-ohm twin-lead for the feeder is recommended over 300-ohm for improved strength and reduced losses, especially in adverse weather conditions. This design, originally published in _RadCom_ in 1993 and featured in Pat Hawker’s "Antenna Topics," provides a compact and efficient solution for HF operation, particularly for those with limited space or resources.
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F6EZX presents a detailed account of constructing a compact, multi-band _Levy antenna_ for portable holiday operations, specifically addressing issues with local QRM from a previous _Deltaloop_ setup. The article outlines the design criteria, including multi-band operation on 40m, 30m, 17m, 15m, 12m, and 10m, a symmetrical configuration to reduce interference, and a low take-off angle for DX. Construction involves 2x 10.3m radiating elements and a 15.3m open-wire feeder (ladder line) with 7cm spacing, made from 1.5mm2 copper wire and foam pipe insulation spacers. Theoretical calculations, referencing F9HJ's "_Les antennes Levy_" book, guide the determination of element lengths and feeder impedance characteristics, aiming for a good match across bands with a commercial antenna tuner. Initial field tests with the _VCI Vectronics VC300DLP_ tuner showed a 1:1 SWR from 80m to 10m, with some difficulty on 17m. The antenna, mounted as a 45-degree slopper with the high point at 12m, successfully facilitated DX contacts to South America, particularly Chile and Argentina, suggesting a lower take-off angle compared to the previous Deltaloop which favored Brazil. The Levy antenna significantly reduced TVI/RFI, attributed to its improved symmetry and greater distance from the QRA. While signal reports on 15m and 20m were 1-2 S-points lower than the Deltaloop, its performance on 40m and 30m was comparable, fulfilling the design goals for a portable, low-cost, multi-band solution.
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Presents G0GSF Brian's ZS6BKW antenna, a refined iteration of the classic G5RV, offering improved performance across multiple HF bands. The design emphasizes specific radiator and ladder line lengths to achieve lower SWR on 40m, 20m, 17m, 12m, and 10m, making it a practical choice for operators seeking a single wire antenna solution. The document includes critical dimensions for the flat-top and the 450-ohm ladder line section, which are key to its multiband resonance characteristics. Unlike the original G5RV, the ZS6BKW aims for direct 50-ohm feedpoint impedance on several bands, reducing the need for an external antenna tuner. My field experience with similar optimized dipoles confirms that precise construction, particularly the ladder line length, is paramount for realizing the intended SWR benefits. This design offers a compelling alternative for hams with limited space or those preferring a less complex antenna system.
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Rugged, disguised 2m, 220MHz, 440MHz, and 2m/440 dual band antennas, HF portable antennas, portable dipoles.
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The 6 Band Inverted L Antenna MK3 is a versatile multiband antenna designed for amateur radio operators. This antenna covers 160m, 80m, 40m, 20m, 15m, and 10m bands, making it suitable for a wide range of HF communications. The design is based on a W3DZZ configuration, incorporating traps for optimal performance. The MK3 version features a sturdy 5/8th CB mast, replacing the original timber mast, which enhances durability against harsh weather conditions. The antenna's construction allows for effective operation, particularly on the 40m band, where it has been successfully used to contact distant locations including ZL, VK, and Antarctica. Constructing this antenna requires careful attention to detail, especially regarding the radials and grounding. The traps resonate at specific frequencies, and additional resources are available for building coaxial traps. The antenna is designed to work efficiently without an ATU on the lower bands, while higher bands may require tuning. This project is ideal for both beginner and intermediate operators looking to enhance their station with a reliable multiband antenna.
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A 40m through 20m QRO End Fed Half Wave Antenna Coupler by Steve Yates - AA5TB
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The Chameleon V1 HF Multiband Antenna is a mobile antenna that can also be used as portable. Lightweight mil whip antenna system with 10 BANDS capability 6m, 10m, 12m, 15m, 17m, 20m, 30m, 40m, 60m & 80m.
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Simple DIY stealth apartment antenna for 20m and 40m. It is basically a ZigZag quarter wave dipole antenna
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An homemade portable vertical antenna with a trap near the mid point of the main element. The trap is made with 42mm diameter PVC pipe with 9 turns of wire on it
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JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.
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This resource details the computer-optimized design of the _ZS6BKW_ multiband dipole, an evolution of the classic _G5RV_ antenna. It begins by referencing the original 1958 RSGB Bulletin article by Louis Varney G5RV, explaining the operational principles of the G5RV's flat-top and open-wire feedline on 20m and 40m, noting its impedance transformation characteristics for valve amplifiers of that era. The article then transitions to the rationale for optimizing the design for contemporary solid-state transceivers requiring a 50 Ohm match. The core of the project involves using computer modeling to determine optimal lengths for the flat-top and matching section, aiming for a VSWR of less than 2:1 on multiple HF bands. It discusses the process of calculating feedpoint impedance based on antenna length and frequency, referencing professional literature from Professor R.W.P. King at Harvard University. The analysis also considers the characteristic impedance (Z(O)) of the open-wire line, identifying a broad peak of adequate values between 275 and 400 Ohms. Specific design parameters for the improved ZS6BKW are presented, including a shorter flat-top and a longer matching section compared to the original G5RV, with a velocity factor of 0.85 for the 300 Ohm tape. The article confirms acceptable matches on 7, 14, 18, 24, and 28 MHz bands when erected horizontally at 13m, and also discusses performance in an inverted-V configuration, noting frequency shifts. The author, Brian Austin ZS6BKW, emphasizes the antenna's suitability for modern 50 Ohm coaxial cable without a balun.
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The ZS6BKW wire antenna, a variant of the G5RV, utilizes a specific 13m (42.6 ft) length of 450-ohm window line as its matching section, feeding a 28.5m (93.5 ft) flat-top element. This design aims for lower SWR on 40m, 20m, 17m, 12m, and 10m compared to a standard G5RV, often achieving SWR values below 1.5:1 on these bands without an antenna tuner. The feedpoint impedance transformation provided by the window line allows for direct connection to 50-ohm coax on multiple bands. F4FHH's experience involved constructing the ZS6BKW and evaluating its performance against an _OCF dipole_ (Off-Center Fed) on various HF frequencies. The article includes observations on SWR readings and operational effectiveness, highlighting the ZS6BKW's suitability for multi-band operation. The antenna's overall length, including the flat-top and window line, is approximately **41.5 meters** (136 feet), making it a significant wire antenna for fixed station use. Comparative analysis with the OCF dipole provided practical insights into the ZS6BKW's advantages and limitations, particularly concerning bandwidth and tuner requirements.
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A simple 7 bands off-center dipole wire antenna designed to work on 80 meters band and that can cover also 40m 30m 20m 15m 12m 10m with acceptable SWR
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A Half wave antenna has a high impedance feed point. This can be matched using a 1/4 wave stub matching section and converts the 40m vertical into an L-shaped 20m J-Pole antenna. The 300 ohm feeder used for this purpose must be kept away from the ground.
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The ZS6BKW antenna, a popular multiband wire antenna, offers improved band matching compared to the traditional G5RV. This construction guide details the process, beginning with specific dimensions: 13.11 meters (43 feet) for the 450-ohm ladder line and initial dipole arm lengths of approximately 14.8 meters each. It emphasizes the critical role of an _antenna analyzer_ for accurate tuning, particularly for determining the velocity factor of the ladder line and achieving a 1:1 impedance match. The article outlines the materials required, including a 1:1 current balun, 450-ohm window line, wire for the dipole arms, and a 50-ohm non-inductive resistor for testing. It provides a step-by-step procedure for cutting the ladder line to its electrical half-wavelength, explaining how to calculate the velocity factor using measured and free-space frequencies. For instance, a measured 50-ohm impedance at 12.54 MHz with a calculated free-space half-wavelength frequency of 11.44 MHz yields a velocity factor of 0.91. Final adjustments involve hoisting the antenna to its operational height and fine-tuning the dipole arm lengths to achieve optimal SWR, specifically targeting 14.200 MHz. The _ZS6BKW_ design is noted for its performance on 80m, 40m, 20m, 10m, and 6m, though it is not optimized for 15m operation. The author, _VK4MDX_, shares practical tips for durable construction using stainless steel wire and cable clamps.
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This article describes a simple Inverted L antenna for the HF bands designed to work on 80m, 40m, 30m and 20m
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A bazooka antenna design in German with dimensions for 20m and 40m band with RG174 coax cable stronger than the common RG58
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An off centre fed dipole, with 10 feet of vertical radiator. It needs no tuner on 40m, 20m and 10m by M0UKD
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Operating an 80/40/20M fan dipole for DX is analyzed through EZNEC modeling, focusing on the antenna's performance in a real-world, low-height installation. The resource details the physical construction and SWR measurements of the fan dipole, comparing them against EZNEC simulations. It also incorporates High Frequency Terrain Analysis (HFTA) data to illustrate typical DX elevation angles for various regions from New England, providing a crucial context for evaluating antenna patterns. The analysis presents EZNEC-generated azimuth and elevation patterns for each band (80M, 40M, 20M) at specific frequencies, showing gain figures at different elevation angles relevant to DX propagation. It compares the modeled SWR with measured SWR, attributing discrepancies to coax attenuation. The study concludes with observations on the antenna's azimuth performance (omnidirectional within ±1.5 dB) and its less optimal elevation gain at desired DX angles, highlighting the impact of low antenna height on DX capabilities.
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An homemade fan dipole antenna for 20 30 40 meter bands, setup in a 15 meter wide garden. The longest leg for 40 meter is folded to fit in the 7.5 m
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Demonstrates the construction and implementation of a **two-element phased vertical array** for 40 meters, utilizing _Christman phasing_ techniques. The author, W4NFR, details the process from building individual 1/4-wave aluminum verticals to integrating them into a phased system. The resource covers antenna spacing of 32 feet, elevated radial design, and the critical steps for tuning each vertical to achieve a 1.1:1 SWR before combining them. It also provides insights into calculating precise coax lengths for feedlines and the phasing delay line, emphasizing the use of an MFJ-269 Antenna Analyzer for verification. The finished system exhibits good front-to-back nulls, with an overall SWR ranging from 1.6:1 to 2.2:1, which is managed by an antenna tuner. The project includes detailed photos of the relay box, showing 12 VDC relays capable of handling 5KV, and the control box in the shack for switching between three different antenna pattern configurations. Static bleed-off chokes are incorporated for protection, and the construction emphasizes robust weatherproofing for outdoor elements.
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A simple to build full length 20/40 dipole antenna to be used in inverted vee configuration
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Designing and constructing portable wire antennas for HF operations, this resource explores several configurations including the _foldback dipole_ for space-constrained setups and an inductively shortened dual-band dipole for 20m and 40m. It details the calculation of inductance for shortened elements, providing a Visual Basic 6.0 program screenshot that illustrates determining coil parameters like turns and length for a **25.5 uH** inductor. The document emphasizes practical considerations such as adjusting wire lengths for optimal SWR, noting that a dual-band dipole achieved SWR below 2:1 on both 20m and 40m, with careful adjustment bringing it under 1.5:1. Further, the resource describes a half-wave antenna matched with a coaxial stub, a method often referred to as the _Fuchskreis_ in German amateur radio circles, to transform the high feedpoint impedance to 50 Ohms. This monoband solution, for a 20m application, uses a stub length of **2.98m** (0.216 lambda multiplied by coax velocity factor) and a shorted stub of approximately 48cm. The coaxial stub design is highlighted for its resilience to ground proximity, allowing it to be rolled up or laid on the ground with minimal SWR impact, making it highly suitable for portable QRP operations.
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Amateur Radio 40m 20m 15m Half Wave Fan dipole antenna project with part list, pictures and drawing. Includes the option to expand the antenna to cover the 80 meters band
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Documents the OC1I and OC6I IOTA DXpeditions to Peru, specifically highlighting operations from SA-098 (Isla La Leona) and SA-076 (Isla Lobos de Afuera). The OC1I team logged over **8000 QSOs** from SA-076, while OC6I made 1400 QSOs from SA-098, despite challenging propagation conditions. The resource details the equipment used, including an _IC-7000_, an IC-706mkIIG, and a TS-440SAT, along with various antennas such as a 160m dipole, FD4, G5RV, and a multi-band vertical for 17m, 20m, 30m, and 40m. The DXpedition dates are specified: OC6I operated from SA-098 between December 28 and December 30, while OC1I was active from SA-076 from January 2 to January 7. Both operations are confirmed as valid for IOTA credit. The page also includes a video link for the OC6I operation and a photo gallery from the DXpedition. Feedback is welcomed, and the webmaster is identified as Bodo Fritsche, DL3OCH.
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Designing and constructing a two-element receiving loop antenna array for HF operation involves specific considerations for achieving high directivity and noise reduction. This resource details a homebrew system comprising two 30-inch diamond-shaped loops, spaced 20 feet apart, which are fed through mast-mounted preamplifiers and passive signal combiners. The operational principle relies on adjusting phase delays between elements via precise _Belden 8241_ coaxial cable lengths, optimized for specific bands from 160m to 20m. Performance data, derived from _EZ-NEC_ modeling, illustrates consistent 90° azimuth-plane beamwidth and low take-off angles across the target bands, with _Receiving Directivity Factor_ (RDF) values comparable to a 300-foot Beverage antenna. The article presents detailed elevation and azimuth plots for 20m, 30m, 40m, 80m, and 160m, demonstrating the array's ability to provide strong response at low DX angles while also supporting _NVIS_ signals. Key components like the _DX Engineering RPA-1_ preamplifier and _DXE RSC-2_ signal combiner are discussed, alongside the importance of impedance matching to preserve antenna patterns. The construction emphasizes self-contained elements that do not require ground radials, offering a compact solution suitable for suburban environments and stealth installations, with a focus on optimizing receive performance independently from transmit antennas.
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Constructing an End-Fed Half-Wave (EFHW) antenna offers a practical solution for HF operators seeking a multiband wire antenna without the need for extensive radial systems. This design typically employs a high-impedance transformer at the feed point, matching the antenna's inherent high impedance to a 50-ohm coaxial feedline. The article specifically details a 2012 approach, focusing on a transformer with a 49:1 turns ratio, which is a common configuration for EFHW antennas. The resource outlines the construction of a wire element cut for a half-wavelength on the lowest desired band, with specific coil arrangements enabling operation on harmonically related bands such as 40m, 20m, and 10m. It discusses the physical dimensions and winding details for the matching transformer, often utilizing a ferrite toroid core to achieve the necessary impedance transformation. The content provides insights into the operational principles and practical considerations for deploying such an antenna, including methods for tuning and optimizing performance across multiple amateur radio bands. While acknowledging that the presented information from 2012 may be superseded by newer insights, it serves as a foundational reference for understanding EFHW antenna theory and construction.
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Author experiments end fed half wave antennas using common two conductore speaker wire, this article features a couple of end-fed halfwave wires for the 40M and 20M bands.
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Presents various amateur radio topics through blog posts, detailing operational experiences and technical insights from the perspective of SV2YC. The content frequently discusses antenna projects, such as a **portable 20m/40m dipole** designed for rapid deployment, and explores the performance characteristics of different wire configurations in varied field conditions. Observations on propagation and band activity across the HF spectrum are also regularly documented, providing practical context for fellow operators. Specific entries often include detailed accounts of **DX contacts** and participation in minor contests, outlining station setup, power levels, and antenna choices. The blog also covers modifications to commercial transceivers and homebrew accessory construction, offering practical advice on improving station efficiency and functionality. Further posts delve into software applications for logging and digital modes, sharing configurations and operational tips for maximizing their utility in daily amateur radio activities.
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Constructing a dual-band antenna for 40 and 20 meters often involves compromises in size or complexity. This resource presents a compact _open sleeve dipole_ design that addresses these challenges by using 450-ohm ladder line and folded elements to achieve a total length of approximately **17.17 meters**, significantly shorter than a full-size 40-meter dipole. The design leverages electromagnetic coupling, where a primary radiator handles the 40-meter band, and a second conductor resonates on 20 meters without direct electrical connection. This configuration eliminates the need for traditional traps, loading coils, or switching components, simplifying construction and reducing potential loss points. The antenna is fed with RG-58C/U coaxial cable, and a common-mode choke is recommended at the feed point to suppress sheath currents, ensuring a cleaner radiation pattern and minimizing RF in the shack. The design is well-suited for portable operations, field deployments, temporary installations, and restricted urban environments where space is a premium, offering solid performance on both HF bands.
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A mircovert antenna assembled for the 40m version of the DL7PE antenna. A one meter long aluminum tube with 24mm diameter is used for the base (element 1) and a 50cm aluminum tube with 20mm diameter for element 2 (the extention). A pvc pipe, 34cm long and with a diameter of 38mm, is used to wind the coil on (1mm enamelled copper wire).
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Operating as FY/F5UII, Christian F5UII conducted a DXpedition to French Guiana (FY) from January 13 to 30, 2013. The primary operation utilized the FY5KE radio club station in Kourou, with activity focused on voice modes during specific weekday hours. The resource details the operator's intent to transmit before 12:00z and after 22:00z, or as availability permitted, from the mainland. A significant aspect of this operation involved a dedicated weekend activation of the Salut Islands, specifically **IOTA SA-020**, from January 19-20, 2013. This segment of the DXpedition was conducted from Royal Island (Ile Royale), part of a group including Devil's Island (Ile du Diable) and St. Joseph Island (Ile Saint Joseph), located 14 km offshore from Kourou. The station setup for the IOTA activation included 100 Watts of power, a GPA-030 vertical antenna for 10m, 15m, and 20m, and dipole antennas for 17m and 40m, with antenna deployment contingent on site conditions and propagation. The operator anticipated strong interest for the SA-020 entity.
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Listen to online WebSDR located in Andorra Europe. Four receivers on 60m, 20m, 40m, and 80m, connected to a dipole antenna direction East/West
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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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The author reflects on expanding their antenna for 80m coverage during lockdown. They extend the End Fed Half Wave (EFHW) using a Spiderbeam pole and "cheating" by dog-legging across their garden. Despite challenges, they achieve coverage for multiple bands with minimal cost. Practical Wireless features EFHW antennas, including a pre-made 20m EFHW extended for 40m.
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How to Design and Build a Field Expedient End-Fed Half-Wave Antenna for 20m, 40m and 80m. This Shorty 80m EFHW comprises a 49:1 autotransformer (to match the very high impedance at the end of a half-wave wire), a half-wavelength wire for 40m (also a quarter-wavelength for 80m), a loading coil and a short tail wire. The coil and the short tail wire (about 6 feet) make up the other quarter wave on 80m.
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Schemaric diagram for a 80m, 40m, 30m, 20m EFHW Antenna Antenna Tuner. The tuner has been designed for an antenna length of 41m and the counterpoise 7.5m.
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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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This study details a reception comparison between vertical and horizontal active loop antennas, specifically two identical _Wellgood active loop antennas_, on various HF bands. The experiment, conducted in a densely populated QRM-prone area, monitored FT8 signals over a 24-hour period using two identical receivers. The methodology involved direct comparison of signal reception across the HF spectrum, aiming to identify performance differences based on antenna orientation. The results indicate that vertical loops demonstrated superior performance on higher bands (10m, 15m, 20m), while horizontal loops excelled on lower bands (30m, 40m, 160m), particularly for receiving long-distance (DX) signals. The horizontal loop's advantage on lower bands is attributed to potentially better low-angle performance and reduced sensitivity to man-made noise, yielding a **2-3 S-unit** improvement on 160m. The study provides practical insights for optimizing antenna placement in challenging urban environments, noting that the horizontal loop consistently showed a **10-15 dB** signal-to-noise ratio improvement on lower bands.
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From March 2 to March 11, 2018, a Norwegian team operated as Z2LA from Zimbabwe, focusing on 160m through 10m bands using SSB and CW modes. The operation, described as "holiday style," aimed to provide contacts for DXers worldwide seeking a rare DXCC entity. Key equipment included a SUNSDR PRO II, an Elecraft KX3, and an Icom 706 MK2G as a spare radio, supported by two Juma 1000 amplifiers for robust signal output across the bands. Antenna systems were tailored for multi-band operation, featuring an Inv L for 160m and 80m, sloping dipoles for 30m/40m, and a _Hexbeam_ from SP7IDX Technology covering 20m to 10m. For improved reception, the team deployed a SAL 30, two reversible BEV antennas from remoteqth.com, and a BOG from K1FZ, enhancing their ability to hear weak signals. QSL information directs operators to Clublog for log search and M0OXO Charles for OQRS, explicitly requesting no bureau cards. The team comprised LA7THA Rune, LA7WCA Arne, and LA9VPA Thor, successfully making numerous contacts and contributing to the DX community's pursuit of _Zimbabwe_ as a DXCC entity.
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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.
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PH0NO conducted field tests comparing a mobile antenna (DX-UHV) to an end-fed half-wave wire. Results on 20m showed the end-fed wire outperforming the mobile antenna, with a significant difference in signal strength. On 40m, the end-fed wire surpassed the mobile antenna in spots and reach. While the mobile antenna is more practical, the end-fed wire offers superior performance. Further testing is planned.
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This **PDF report** documents a _maritime mobile_ DXpedition operating from the _Southern Ocean_ near Antarctica, detailing antenna deployment strategies on a sailing vessel. It addresses power management systems for remote operations and propagation characteristics specific to polar regions on **20m and 40m** bands. Operational strategies include managing high-density pileups using split frequency operation and maintaining signal integrity during periods of high aurora activity. Equipment considerations cover specific transceiver models like the Icom IC-7300, antenna types optimized for marine vessel installation, and battery power systems for extended periods without shore power. The resource also examines the use of satellite communication for real-time log uploads and QSL confirmation from remote locations, and discusses mitigating signal degradation from ice accumulation on antennas. DXZone Focus: PDF report | Maritime Mobile DXpedition | Polar Propagation | Split Frequency Operation