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Optimizing low-band signal performance for contesting and DXing often involves complex antenna systems. This resource presents the FVR Spitfire Array, a "poor man's 4-square" design specifically engineered for the 80-meter and 160-meter bands. The core content is a PowerPoint presentation originally delivered at the 1998 Dayton Hamvention, outlining the design principles and practical considerations for this phased vertical array. The FVR Spitfire Array aims to provide directional gain and improved signal-to-noise ratio on the lower HF bands without the need for a large, rotatable Yagi. The design focuses on achieving effective directivity and pattern control using vertical elements, a common approach for enhancing receive and transmit capabilities on 160m and 80m, where full-sized Yagis are impractical for many stations. The presentation likely covers construction details, phasing networks, and expected performance characteristics. Further information is provided through an additional FAQ document, addressing common questions and offering clarifications on the array's operation and implementation. This supplementary material helps operators understand nuances of the design and troubleshoot potential issues, making the project more accessible for those looking to build or adapt the FVR Spitfire Array for their own station.

Freeware antenna software that lets you see what the polar diagram of your rotatable beam actually looks like where it is operating. With PolarPlot you can measure the polar diagram of the antenna and check for abnormalities - compare plots taken before and after changes to the design or location - check the -3dB beamwidth - look at the front to back ratio - see the size and position of the sidelobes.

An excellent all-around 40 meter antenna for those who don't have room for a multi element yagi antenna

This article describes a simple, inexpensive, dipole antenna that will rival the performance of a ten-meter beam.

For radio amateurs seeking compact, directional antenna solutions, the Moxon Rectangle offers an attractive alternative to traditional two-element Yagis. This resource compiles several articles by L. B. Cebik, W4RNL, exploring the **Moxon Rectangle** design, which provides gain comparable to a full-size two-element array but with a significantly improved **front-to-back ratio** and a direct 50-Ohm feedpoint match. The collection covers both wire arrays, particularly for lower HF bands, and rotatable aluminum beam constructions, addressing various aspects of this popular antenna configuration. The articles delve into specific band applications, including designs for 10 meters, 40 meters, and 2 meters, alongside discussions on multi-banding techniques and pattern characteristics. Comparisons are drawn between the Moxon and other antenna types, such as VK2ABQ Squares, highlighting the Moxon's advantages in terms of size and performance. Practical construction notes are provided for both wire and aluminum versions, offering insights into building these antennas for different operating environments.

Multiband and monoband HF Vertical antennas and rotatable dipoles manufacturer based in Texas USA

Presents a construction project for a linear-loaded 40-meter rotatable dipole, detailing the design evolution from mid-element coils to 300-ohm twinlead loading. It covers material selection, including repurposed fishing poles and EMT conduit, and outlines the assembly process for the antenna elements and mounting plate. The resource provides specific measurements for element lengths and linear loading sections, along with SWR plots demonstrating the antenna's resonance at 7.035 MHz with a 1.1:1 SWR, and bandwidth up to 7.120 MHz below 2:1 SWR. The article documents the antenna's performance during various RTTY and CW contests, including the SARTG RTTY and SCC RTTY contests in August 2006, and the ARRL DX CW and CQWW WPX RTTY contests in February 2007. It reports successful operation at 500-1000W, noting improved performance after replacing a faulty coax cable. Specific DX contacts from British Columbia, including stations in Europe and South Africa, are listed, illustrating the antenna's capability despite its shortened length and relatively low height of 55 feet. The content highlights practical considerations such as weatherproofing the connections and supporting the fiberglass elements to prevent sagging. It also includes a brief comparison to an inverted-V at similar height and a ground-mounted vertical, noting the rotatable dipole's quieter reception. The author shares insights into the iterative design process and tuning adjustments made to achieve optimal resonance.

Construct a compact, 20 meter rotatable dipole antenna of durable weather worthy components supported at a single point obviating the need for multiple supports and multiple support ropes crossing the yard.

Rotatable Antenna with Phased Elements based on the orignal design concept of HB9CV antennas, is considered to have an higher gain than standard quad antennas. The Swiss Quad Antenna does not need any spreader or boom.

Experimenting a 20 40 meter short coil loaded dipole antenna with the goal to keep the total length under 40 feet so that the dipole can be mounted on two 20 foot fiberglass pole to make a 20/40 meter rotatable dipole.

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.

The document details the construction and performance of a rotatable flag antenna designed for a small lot. The 7x14 feet flag, built with fiberglass poles and an aluminum hub, shows improved reception compared to the author's previous transmit antenna. Key components include a conventional transformer for impedance matching and a variable resistance termination system to optimize performance. Despite challenges like nearby objects affecting signal patterns, the antenna consistently provides better signal-to-noise ratios, making it a valuable addition for low-band listening in suburban areas.

The article discusses the evolution of antenna designs, specifically focusing on the upgrade from the W7IUV rotatable Flag to the Waller Flag. Author Pierluigi Mansutti IV3PRK shares insights on modeling these antennas using EZNEC software, detailing their performance in noisy environments. The W7IUV Flag proved effective for receiving signals, while the Waller Flag, developed by NX4D and N4IS, offers improved front-to-back ratios but requires careful consideration of signal levels and noise management. The article emphasizes practical modeling results and interactions between different antenna setups.

This project describes a high-performance EME antenna array consisting of two home-designed 9-element Yagis, each about 2.5 wavelengths long, combined into a 25-ohm system and matched to 100 ohms using 9/4λ sections of 50-ohm coax. The array supports rotatable polarity from 0° to 180°, allowing both horizontal and vertical polarization to optimize moonbounce performance under varying conditions. Despite operating for years without a balun—something another designer called “disastrous”—the system has delivered strong results, including copying very weak DX such as VK3KH at about -25 dB with only 120 W (around 2 kW ERP). The builder continues to refine the mechanics, having installed new gear motors and an upgraded follow-up control system in 2011.