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For radio amateurs seeking compact and efficient antenna solutions, particularly for restricted spaces or noise reduction, HF loop antennas present a viable option. This resource compiles several articles from the ARRL, detailing the theory, design considerations, and practical construction of various loop configurations. Topics include small transmitting loops, receiving loops, and multi-band designs, often emphasizing their performance characteristics such as directivity, bandwidth, and impedance matching. The collected articles provide insights into the comparative performance of different loop geometries, such as circular versus square loops, and discuss the impact of conductor size and tuning methods on efficiency. Practical applications are explored, including their use in portable operations, stealth installations, and urban environments where noise mitigation is critical. The content often includes construction diagrams, parts lists, and performance data derived from modeling or field tests, enabling hams to replicate or adapt the designs for their specific operating conditions.

This project produces an inexpensive, multiband, end fed HF antenna matchbox, quick and easy to setup. This project creates a trifilar wound, 9:1 UNUN toroid matching transformer. Handles 100W and need an antenna tuner.

Online helix antenna designer, calculate size of helix antennas online

Fractal antenna for 28 Mhz band by AG1LE

Working priciple of OSJ and jpole anntennas by PY4ZBZ

EB4EQA's Projects GSM1800 moxon square antenna

Many antennas function because of common mode currents, rather than working in spite of them. Two popular examples are CFA and EH antennas. Another recent example, appearing in Antennex's compact antenna articles, is a thick stub "vertical" with no counterpoise.

w4kaz antenna swicth

by Adam M. Farson VA7OJ/AB4OJ

Phased vertical antenna system in french

The DL6WU yagi antenna for 23cm band

Slot antenna and complementary dipole

Antenna experiment - Delta Loop for 7 Mhz band by AG1LE

This is an Excel spreadsheet template to design DL6WU Yagi antennas

Homebrew Wifi antenna test page

A 2 meter antenna made of copper tubes, offering circular polarization

An easy method for erecting antenna masts using readily available material

The page discusses Axial-Mode Helical Antennas, focusing on turning helical antennas over perfect ground and modeling helices in NEC-2 for optimized design. It covers topics such as high-gain performance, broadband, impedance matching, radiation pattern, feedline, balun, near field, far field, and DIY applications.

The aim of the project is test if fractal antennas can work acceptably on HF bands.

A german documento on magnetic loop antennas

This article describes the 144MHz horizontally polarised antenna at VK1OD in November 2008. The antenna uses two identical four element arrays that were constructed around 1970

G3TPW CobWebb Antenna for the 14, 18, 21, 24 and 28 MHz Bands

About HF Wire Antennas for field day or any day a basic wire antenna article

The problem with making your own trapped HF antennas is usually getting the coaxial traps tuned to frequency.

A moxon antenna for 11 meter band, suitable for 27 Mhz and 28 Mhz

Demonstrates the product line of _LZ Antenna Ltd._, a Bulgarian manufacturer specializing in amateur radio antennas and custom electronic devices. The company focuses on robust, high-quality HF multiband Yagi and vertical antennas, leveraging over 20 years of experience from founder Georgi Georgiev in radio amateur development. Featured models include the LZA 8-4, LZA-10-3, and the LZA-7-3A WRTC 2022, alongside various rotary dipoles like the LZA1 40/30m. Provides specifications for several Yagi antennas, such as the LZA-9-5, LZA-13-7, and LZA-6-3 (a 6-element, 3-band design). The company emphasizes applying "leading edge technology" to high-frequency communication equipment production, with products designed for durability and performance. The LZA-10-5 Yagi offers **12.5 dBi** gain on 10m, while the LZA-13-7 provides **13.2 dBi** on 20m, showcasing competitive gain figures for DXing and contesting.

Helical antennas have long been popular in applications from VHF to microwaves requiring circular polarization, since they have the unique property of naturally providing circularly polarized radiation. Paul Wade W1GHZ

This HALO design is not ground dependent and can be mounted atop a section of PVC.

New type of a Quad antenna, 6.4dBd gain

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.

Various publications through the years have shown how the SWR measured on a shorted (or open) feed line can be used to calculate feed line attenuation

A 10 meters band Slim Jim antenna project, made with a 450 Ohm slotted ribbon cable and secured on a 8 m fishing pole, by Steve G0KYA

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

Stacking 2 Meter Halo Antennas by Mike Fedler N6TWW

A moxon antenna project for 70 cm band, test and results of this popular antenna model applies to UHF bands.

A 4 way remote antenna switch project

W4ZT used this antenna for Field Day and other portable applications. He built them for all bands between 160 meters and 6 meters. You can make them easily using whatever wire you have available and make the insulators from scrap plastic

The Truth about the G5RV Antenna, how to optimize the design to be more efficient on all bands

Antenna mounting height, the higher the better? Learn how radiation pattern change, and decide if you need an higher or a lower angle for your dx needs.

Constructing a portable, high-gain antenna for _AO-40_ satellite operations presents unique challenges, particularly regarding mechanical stability and parabolic accuracy. This resource details the build of a 1.2-meter "brolly dish" antenna, utilizing a non-conducting fiberglass umbrella frame as its foundation. The project outlines a method for achieving a parabolic shape using stressed aluminum fly screen mesh, guided by practical geometry and a temporary dowel template. Key steps include selecting an appropriate umbrella with a suitable f/D ratio (ideally >0.25), removing the original fabric, and precisely cutting and attaching eight segments of fly screen to the struts to form the reflective surface. The construction process, which took approximately five hours for the author, _G6LVB_, resulted in a dish with an f/D of 0.27 (depth=270mm, diameter=1160mm, f=310mm). The article also describes a modification to a _TransSystem AIDC_ feed, incorporating a PCB reflector behind the dipole for easier mounting. Performance tests at a squint angle of 15 deg and a range of 50,000km yielded a signal-to-noise ratio of 33dB on the S2 beacon and 23dB for SSB signals, indicating strong reception. The author notes that the modified umbrella may not close fully without risking surface disfigurement.

The WT0G crazy W dipole, a solution for 160 meter operations

There is considerable confusion as to what exactly a multiband vertical antenna is. The confusion concerns the method of feed, how much mismatch one can expect, how many radials are required, how the particular antenna is built for multiband use, plus some other points.

A vertical portable antenna system by W0SJS that will work on 40, 30, 20, 17 and 15 meters

Lowering an NVIS or N.V.I.S. antenna very close to the ground enhances NVIS operation

This antenna was described by Bill, G4KIH in Sprat 52 and is actually a G5RV modified to fit into a small space.

A project of a semi vertical trap antenna that can be tuned for 7 bands

A project of a vertical and wires that generate a multiband antenna for 28 14 10 and 7 Mhz in french

Antenna tests on Alford 1.2 Ghz for ATV oprations in italian

A compact halfwave endfed wire antenna tuner that works 12 thru 40 meters with a halfwave wire for the band of interest attached

A Quad Loop antenna for 17 meter band