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A receiving loop antenna for low frequency DX Work

This antenna can gets you on the air on 14MHz, and it has a useable frequency range. The VSWR is almost perfect at the centre-frequency abd the design uses no expensive components.

Magnetic Loop antenna for 20 to 80 meters band using home made butterfly condensator kit

Octagonal magentic loop antennas that work from 20 to 10 meters with pictures and efficiency reports by G1KEA

Article from 73 Amateur Radio Today about experimenting on ferrite loops transmitting loop antennas for 80 and 160 meters bands.

Simple 6 Metre DX Antenna based on an article by LB Cebick in QST May 2002 on a Quad Turnstile antenna. This antenna is basically two full wave loops mounted at right angles fed 90 degrees out of phase to produce an omni-directional horizontally polarized pattern

A dual band delta loop antenna resonating on 30 and 40 meters band using a single wire for the top slopers on both 30 and 40 meters and does not need any balun

A few pictures of an homebrew magnetic loop RTX antenna project, working from 30 to 12 meters with excellent results

An almost invisible wire antenna for the 17 meters band

Home-Made Magnetic Loop Antenna for 30 Meters by WA8LMF

Operating a ham station often involves encountering radio frequency interference (RFI), RF feedback, or RF burns, which are frequently misattributed to poor equipment grounding. This resource meticulously dissects these assumptions, asserting that RF grounds on the operating desk often merely mask more significant system flaws. It identifies five primary causes for RF problems, including antenna system design flaws, proximity of the antenna to the operating position, DC power supply ground loops, equipment design defects, and poorly installed connectors or defective cables. The content emphasizes that issues like "hot cabinets" or changes in SWR when connecting a ground indicate substantial RF flowing over wiring or cabinets, a phenomenon known as common-mode current. The article provides detailed explanations of common-mode current generation, particularly from single-wire fed antennas like longwires, random wires, and OCF dipoles, which inherently present high levels of RF in the shack. It also illustrates how vertical antennas, lacking a perfect ground system, can excite feed lines with significant common-mode current. Through simulations, the author demonstrates how a dipole without a proper _balun_ can cause RF problems at the operating desk, showing current patterns and voltage distributions on feed line shields. The discussion extends to the proper application of _RF isolators_ and _ferrite beads_, clarifying their role in modifying common-mode impedance on cable shields and cautioning against their use as a band-aid for fundamental system defects. The resource advocates for correcting the actual source of RF problems, such as antenna system issues or poor connector mounting, rather than relying on internal shack grounding or isolators. It highlights that properly functioning two-conductor feed lines, like coaxial or open-wire lines, should result in minimal RF levels at the operating position, even without a desk RF ground. The author shares personal experience, noting that his stations since the late 1970s have operated without RF grounds at the desks, relying instead on proper antenna system design and feed line integrity.

A 2 elements delta loop antenna for 14 MHz with a MMana simulation file, dimensions, pictures of this aluminium tube based delta loop antenna, and matching system details.

US amateur radio antenna manufacturer. Produce baluns, delta loops, dipoles, ocf antennas and more

A Simple Delta Loop Antenna for Smaller Vessels

A shielded broadband (~200 MHz) active loop antenna offers more quiet and relatively less interference reception.

Such kind of omnidirectional antenna gives the possibility to be QRV with horizontal polarisation, as commonly used for the CW and SSB section of the 2m band. This actual design shows a 1.3:1 bandwidth of about 150kHz, centered to 144.200MHz.

This wire antenna for 40 and 20 meter band feature a good SWR. Horizontal side of the antenna is placed at two meters above the ground. Impedance of the antenna are depending by the height of the base from the ground and conditions of the ground

A considerably shortened Magnetic Loop antenna with performance of a single conductor text book magnetic loop.

NRSC AM bandwidth measurements with the loop antenna

A delta loop antenna for 20 meters band designed with MMana with a tuning system made in a classic stub configuration

A low-band receiving antenna that can fits in a 30-foot circle

This article describes the development of two tunable antennas each consisting of three interconnected small loops and capable of providing excellent DX performance. The aerials are home-constructed, and located in a very small garden with a minimum of visual impact on the neighbours and are low enough in height to avoid the attention of UK planning authorities.

A monoband delta loop antenna for the 7 MHz. This vertically polarized DX Antenna is a full wavelength sngle side antenna and has a total length of 42.3 meters (137,1 inch) Can be easily setup with a flag pole or fishing pole as center top mast. For optimal performance lower side should be at 2 meter above the ground. This antenna offers a low radiation angle and 1 DB Gain.

Low Band Receiving Antenna, it is a ground independent Receiving antenna which only needs two 10m support poles by DH1TW

Consider installing a stealth vertical loop antenna if you live in a place with no antenna restrictions. Full wave loop wire antennas allow you to be on the air without installing evidente external aerials.

A page describing how to setup a magnetic loop antenna with the DIY Magnetic Loop Starter Kit produced by Chamaeleon Antenna. Includes a video and a detailed instructions to setup.

This antenna is a vertical loop antenna mounted on a 8 meters high grounded mast with an input impedance of 50 Ohms without a matching device

A quad turnstile consists of two cubical quad loops oriented in a diamond configuration and angled 90 degrees apart from one another with both diamonds sharing the same top and bottom points

This project details the construction and testing of a M0PLK Delta Loop antenna for the 20-10m ham radio bands. Inspired by positive reviews highlighting its reduced local QRM compared to Cobweb antennas, the author built the antenna using aluminum tubes, DX-Wire FS2 wire, and a 1:4 balun. A mix of custom 3D-printed parts and careful assembly ensured stability and performance. Initial VSWR measurements met expectations, and test QSOs demonstrated success across multiple bands. Future enhancements include adding a lightweight, remote-controlled rotator for directional capabilities.

A portable (15.5 foot diameter) NVIS loop for 3.5 to 7.3 MHz. Performs well at high and low takeoff angles, and has smaller footprint than most NVIS antennas.

In this article the author shows the receiving loop antenna for 160 meters band installed at his QTH. Diagram and movie available. Article in in Turkish but can be translated in english

A QRSS beacon on 30 meter band project wind and solar powered based on a loop antenna.

This antenna was conceived mainly for high-speed digital transmission via satellite. The antenna is made of two full waves loops , mounted at right angles to each other. Then coupled together, 90 degrees out of phase over a horizontal circular reflector. With this configuration the antenna is omni directional and circularly polarized.

Phased Spaced Active Whips and Broadband Loops by WA1ION

A free Labview antenna calculator program. This interesting calculator for small loop antennas can be ran on most recent Windows versions using the Labview runtime.

The Hentenna is an Asymmetrical Double Rectangle (ADR) Loop Antenna originally designed by Japanese Hams operating on the 6 m Band in the 1970s.

The antenna described in this article is for 50 MHz, but the design can be scaled for any band, including VHF, UHF, or even the higher HF bands. The antenna is nothing more than a square loop of wire, approximately 30" (or ~76cm) per side. The loop is fed in the middle of one side, and the opposite side to the feed point has a gap in it.

A loop antenna for 80 and 40 meters band, the main loop is based by a crossed line using aluminium strip lines. The main loop diameter is 150 cm.

A home made magnetic loop for HF Bands. This small and compact loop is designed to support small power transmissions on HF bands, from 7 MHz to 21 MHz

The Magloop Antenna Calculator was developed to predict the characteritics of a small-loop (aka magloop) antenna, given physical dimensions entered via slider widgets. This magnetic loop antenna calculator works also on most mobile devices, adjusting sliders and calculating dimensions in real time.

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.

An experimental antenna for HF reception. It consists of a single loop element mounted on the ground. It is stealthy, small, and quiet. EZ-NEC plots and on-air test results are included.

An experimento of a 40 meter delta loop antenna both in horizontal and vertical polarization and several elevation angles with interesting notes about the effect of the radial field under the antenna.

This Guide helps you to build the 1:2 BalUn 600 Watts DIY kit step by step. If a delta-loop or quad-loop antenna is powered with a coax cable from the transceiver it is necessary to use a 1:2 BalUn. This 1:2 BalUn uses a symmetrical 1:2 impedance transformer.

Maker of small and compact multiband QRP UltraLight Magnetic Loop Antennas and UnUn transformer for end-fed multiband antennas

A 160 Metre Transmitting and Receiving Thin Wire Magnetic Loop Capable of DX. Designed and Patented by Ben Edginton G0CWT

Quads beams consist of 2 1 wavelength (approximately) loops, ordinarily arranged so that one is the driven element and the other is the reflector. In this project author explains how to build a two element Quad Antenna for the 28 MHz.

A portable operation experience with a SpiderBeam pole during a contest, testing wire antennas, like dipole and delta loops configurations on 20 40 and 80 meters band.

Free ham radio utilities written in LabVIEW includes Open Wire Calculator, Dipole Peak/Null Angle Calculator, a Coil-Shortened Antenna Calculator ad interesting Round Coil Inductance Calculator and a Skyloop Antenna Calculator

A homemade delta loop antenna for six meters band in German