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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.

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.

The M0PLK multiband delta loop antenna project details the construction of a non-resonant, bidirectional antenna designed for 20-10m operation, requiring an external antenna tuner. The design utilizes two 5.65m aluminum tubes arranged at right angles, with 2x 2.80m antenna wires converging into a 2.30m ladder line, feeding a 1:4 balun. The resource provides a comprehensive parts list, including specific dimensions for aluminum tubes (25mm, 20mm, 16mm outer diameter), DX-Wire FS2, and custom 3D-printed components like a middle insulator, tube end caps, and ladder line spacers, with STL files provided. Construction steps cover base plate fabrication from a 300x300x4mm aluminum sheet, balun assembly, tube preparation with slits and threaded holes, and wire attachment with strain relief. Initial VSWR measurements are presented, indicating performance in line with expectations across the target bands. The author reports successful SSB test QSOs to the USA on 10, 12, 15, 17, and 20m immediately after completion. The project highlights the antenna's bidirectional pattern, noting the need for a lightweight, remote-controlled rotator to fully utilize its directional capabilities. Comparisons are drawn to the Cobweb antenna, with the M0PLK design cited for its reduced local QRM pickup. The article references external sources, including M0AWS's detailed report and PC modeling, along with other construction variants and commercial assembly instructions, providing a robust foundation for replication.

This WEBSDR runs on Raspberry PI4-8G, Afedri-Net RX for 160m, RTL-SDR stick with homemade SBL1 mixer upconverter and fullsize 160m Delta loop antenna 4m up. Operated from Ukraine by UR5WT, US5WE and UX5DH,

The tri-band trapped delta loop antenna design operates on 80 meters (3.5–4 MHz), 40 meters (7–7.3 MHz), and 30 meters (10.1–10.15 MHz) using a single triangular wire loop. This configuration eliminates the need for an external antenna tuner or band-switching relays. The antenna's physical perimeter, approximately 270 feet, establishes 80M as the fundamental band, with specific trap placements enabling resonance on 40M and 30M. Trap design and placement are critical, with 30M traps positioned inboard of 40M traps within the horizontal element. Each slant leg measures approximately 80 feet. The resource references foundational information from the _ARRL Antenna Handbook_ and _ON4UN’s Low Band DXing_ regarding full-wave loop behavior and feedpoint impedances. The project aims to provide multi-band HF operation from a single, fixed antenna structure.