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Время работы с 9:00 до 18:00 понедельник - пятница
The Moxon antenna, also known as the Moxon Rectangle, is a compact, two-element directional antenna renowned for its exceptional front-to-back ratio and simple construction. Originally detailed in Les Moxon's (G6XN) seminal work, "HF Antennas for All Locations," this design remains a favorite for amateur radio operators facing space constraints or requiring portable solutions. 1. Understanding the Moxon Design
The Moxon is a specialized version of the Yagi-Uda antenna, consisting of a driven element and a single parasitic reflector. Its unique rectangular shape is achieved by folding the tips of both elements toward each other.
Folded Elements: The folded ends reduce the antenna's width to approximately 70% of a standard two-element Yagi.
Air Gap: A critical air gap between the tips of the driven element and the reflector provides the coupling necessary for its distinctive radiation pattern.
No Impedance Matching: Most Moxon designs are inherently 50-ohm antennas, allowing for a direct connection to coaxial cable without complex baluns or matching networks. 2. Key Performance Advantages
Despite its smaller footprint, the Moxon often outperforms larger antennas in specific environments: Moxon Antenna Array Design and Pattern Synthesis Technique hf antennas for all locations moxon pdf
The Moxon Rectangle, popularized by Les Moxon (G6XN) in his seminal book HF Antennas for All Locations, is a compact, two-element directional antenna favored for its high performance-to-size ratio. Core Design Features
Rectangular Geometry: Unlike a standard straight-element Yagi, the Moxon folds the ends of the driven element and reflector toward each other.
Space-Efficient: The folded ends reduce the antenna's width to approximately 70% of a standard two-element Yagi, making it ideal for restricted spaces.
Direct Feed: It typically presents a near-perfect 50-ohm impedance, allowing it to be fed directly with coaxial cable without complex matching networks like baluns or gamma matches.
Critical Gap: The spacing between the ends of the driven element and the reflector (the "gap") is the most critical dimension for achieving its unique performance characteristics. Performance Benefits The Moxon antenna , also known as the
Exceptional Front-to-Back (F/B) Ratio: The Moxon is renowned for its high F/B ratio (often exceeding 30-40 dB), which effectively rejects unwanted signals from the rear.
Broad Forward Beam: It offers a wide main lobe (often over 100 degrees), making it more forgiving to aim than a narrow-beam Yagi.
Low Angle of Radiation: When mounted correctly, it provides the low radiation angle necessary for long-distance (DX) communication.
Wide SWR Bandwidth: Especially when constructed with tubing, it maintains a low Standing Wave Ratio (SWR) across a broad frequency range. Common Construction Materials (PDF) Design and Development of UHF Moxon Antenna
Invented by Les Moxon, G6XN, the Moxon rectangle is a two-element driven and reflector array. Unlike a standard Yagi where the reflector is a single rod, the Moxon bends both the driven element and the reflector into a "U" or rectangular shape. Tables for 10, 12, 15, 17, 20, 30,
The most cited and respected free PDF is:
“The Moxon Antenna Project” – by L. B. Cebik, W4RNL (SK)
Often republished as “HF Antennas for All Locations – The Moxon Rectangle” by various amateur radio clubs.
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"Moxon antenna" Cebik PDF or "Moxon for all locations" filetype:pdf
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The Moxon is a balanced antenna. If you feed it directly with 50-ohm coax and the antenna is perfectly symmetrical, you may get away without a balun. However, for all locations except perfectly free-space, use a 1:1 current balun (common mode choke) at the feedpoint to prevent the coax from becoming part of the antenna. A stack of 31 ferrite beads over RG-400 is your best friend.
