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This antenna was designed to meet the requirements of a light body worn small magnetic loop covering all the frequencies continuously from 7 MHz to 29.4 MHz

Understanding high-frequency (HF) skywave propagation is crucial for amateur radio operators seeking to optimize long-distance communications. This resource details the fundamental principles of HF radio propagation, including the properties of electromagnetic waves, the characteristics of various HF bands, and distinct propagation modes such as skywave, ground wave, and line-of-sight. It places significant emphasis on the ionosphere's pivotal role in refracting HF waves, explaining how solar activity directly influences ionospheric conditions and, consequently, propagation paths. The resource integrates real-time monitoring capabilities, featuring dynamic charts and data from DX clusters, WSPRnet, and the Reverse Beacon Network, which allow users to track current band activity and propagation conditions globally. It also delves into advanced topics like Near Vertical Incidence Skywave (NVIS) and gray line propagation, providing insights into ionosonde data and various propagation prediction models. The site presents a detailed analysis of solar-terrestrial interactions, geomagnetic indices, and space weather phenomena, illustrating their direct impact on HF communication reliability. Practical tools and applications are highlighted, including real-time QSO planners, online Maximum Usable Frequency (MUF) maps, and alerts for solar flares or geomagnetic storms. The guide systematically breaks down complex concepts into accessible chapters, offering a structured approach to learning about ionospheric regions, diurnal and seasonal effects, and the interpretation of propagation indicators like foF2, MUF, and Lowest Usable Frequency (LUF). This makes it a robust reference for hams aiming to deepen their technical understanding and improve operational effectiveness.

The DXrobot, operational since 1999, offers a free, non-commercial service primarily for the VHF ham radio community. It specializes in automatic real-time E-skip warnings for **144 MHz** in both Europe and North America, delivered via email or SMS. Additionally, the system provides automatic aurora alerts for _50, 70, and 144 MHz_ openings through the same notification methods. Beyond real-time alerts, the DXrobot facilitates the reception of the latest DX-cluster spots via email, a feature useful for operators without immediate WWW or cluster access. The service also displays recent E-skip and aurora spots detected by the DXrobot on 50, 70, and 144 MHz, with updates every five minutes. Historical data includes lists of all DX spots from the previous day on 50, 70, and 144 MHz, updated daily. Key propagation data, such as MUF timeline, Solar X-rays, Geomagnetic Field, and Estimated Kp index, are also presented.

Also known as Magnetic Loop Antennas, by AA5TB. Excellent article on construction tips and tecniques of a Small Loop antenna

Display solar activity forecast for next 27 days, display A-index, Sunspot Numbers and Flux forecast including graphs for solar activity and geomagnetic forecast. All forecasts are updated daily.

Article about magnetic loops, construction notes and diagrams

The Coke Loop is a Small Magnetic Loop Antenna tuned by a trombone-style variable capacitor made with standard soda cans

The Antenna Rotator Controller is unique in that it senses, displays, and controls to the earth's true magnetic field. The compass sensor, mounted in a waterproof enclosure, is attached to the mast and sends its signal to a microcontroller

A well documented article on a small magnetic loop antenna for the 40 meters band

Presents the Light Loop, a small magnetic loop antenna optimized for 40m through 10m operation, demonstrating its construction for portable QRP use. The design emphasizes lightweight materials and a compact form factor, making it suitable for handheld or backpack deployment during field activities. It details the primary radiating element, the coupling loop, and the variable capacitor required for resonance across the specified HF bands. The article provides specific component choices, such as the 1.5-inch diameter aluminum tubing for the main loop and the 10-365 pF variable capacitor for tuning. It discusses the importance of precise loop circumference and spacing for efficient impedance matching and bandwidth characteristics. The resource includes practical advice on achieving resonance and optimizing performance for low-power transceivers. Construction notes cover the mechanical assembly, including mounting the capacitor and feedpoint connections. It highlights the antenna's suitability for pedestrian mobile operations, offering a practical solution for HF communication without extensive setup. The design aims for a balance between portability and effective radiation on the lower HF bands.

A page about a Magnetic loop antenna project for the 40 meters band, includes nice pictures and history of construction

Local and DX contacts from tight spaces, it works from 40 to 17 meters

DF9CY Active Magnetic Antenna project

Portable magnetic loop antennas - G4TPH Mag-loop antennas Reviewed in PW and RadCOM, Both QRP and QRO, Portable. The only Magloop on the market that is fully portable

A magnetic loop antenna calculator made with an excel sheet that run also with open office, let you design mag loop antenna dimensions by AA5TB

An invisible magnetic loop antenna mounted under a table by PY1AHD

A QRP 900 grams hydraulic tuned small magnetic loop antenna by PY1AHD Alex.

A magnetic loop made just of wire. Suitable for portable usage and for QRP operations.

Excel spreadsheet that help calculating dimensions of a high efficiency magnetic loop antenna for HF bands. Giving in input the loop perimeter, loop diameter and loop conductor will calculate electric characteristics, bandwidth, and efficiency

Excellent poster representing the electromagnetic spectrum from 31.2 mHz to 6.52 EHz, PDF file poster designed by Anthony Tekatch

This magnetic loop is 78cm diameter, with the smaller Hertz loop for tuning. Feeding is by gamma match.

Antenne Cadre Project by F5NGZ, description by F5TZA in french

This receive only loop covers a frequency range of about 5 MHz to 22 MHz and is built from readily available parts.

This article describes a loop usable from 7 - 21 mHz, using half inch copper tube 3 feet in circumference

A german documento on magnetic loop antennas

An impedance transformer (9:1) to feed a high impedance long wire (~450 ohm), down to a 50 ohm unbalanced coaxial input.

Compact and efficient magnetic loop antenna that cover from 40 to 10 meters project by G8ODE published by RSARS

A figure-8 double loop antenna

Bill Rinker, W6OAV, handcrafted this compact magnetic HF loop from copper and pvc plumbing supplies, a 12 volt motor, and some teflon sheets. He's had great reports with it.

The Pocket Loop is a small magnetic loop antenna designed for a carry anywhere operation, it disassembles in 33 centimeters pieces that can be carried even on an attach handbag.

March Paddle by K4QU

A magnetic loop antenna using a 28\" bicycle rim for six meter band

A light and portable magnetic loop antenna with improved bandwidth and performance by HB9MTN

RADIOING eEngineer RFI EMI information

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

Although a magnetic loop antenna(aka small loop antenna) is very compact, its efficiency is close to a half-wavelength dipole if carefully built.

Drawing and plan for an HF magnetic loop antenna

Magnetic Loop antenna for broadcasts band reception

This max size magnetic loop antenna for 14 MHz with a totall circumference of 6m is designed to attach to a wall

A magnetic longwire unun with a T130-2 Iron Powder core by M0UKD

Presents the construction of a 6-meter (50 MHz) Moxon wire beam antenna, detailing the use of #14 AWG THNN stranded wire and a treated wood frame. It covers the assembly of a galvanized pipe mast, emphasizing the use of pipe sleeves for joint reinforcement over threaded couplers to prevent breakage during raising and lowering operations. The resource also describes the integration of a 1:1 current balun, rated for 50-54 MHz, and the use of RG-8X coax for the transmission line, recommending low-loss alternatives like Belden 9913-7F. Further, it outlines a manual rotation mechanism using pipe hanger clamps and carriage bolts for true North orientation, incorporating magnetic declination calculations from NOAA. The antenna's performance is discussed, noting good gain and take-off angle, with SWR tuning facilitated by a Palstar AT-500 manual tuner. An EZNEC+ 5.054 model for the antenna is available for download, alongside predicted radiation patterns and SWR curves, compared with actual AIM-4170C measurements.

A homebrew Magmount for 2m antenna

Comparison of performance between an indoor random wire versus a magnetic loop using psk31

Detection and recording of Schumann resonances and other electromagnetic phenomena at frequencies below 50 Hz By Hans Michlmayr

This ia a home built Magnetic loop antenna which was used by G3BGR, indoors on 7,10 and 14Mhz. The basic idea was in Radcom 1986

VK3YE magnetic loop antenna plan that cover 7 Mhz to 20 Mhz and shortening loop can work on 21 Mhz.

A complete guide to magnetic loop antenna construction, with analysis of multi-turn and single-turn magneti loops, and and insight on choosing the optimal capacitor, or homebrewing your own butterfly capacitor

A switchable Magnetic Transformer for Transmitting for various impedances

A monster magnetic loop antenna for 160 meters band. This Magnetic loop is optimized for 1840 Khz + 50 Khz. PDF Article published on La Radiospecola 10.22

A magnetic loop antenna working from 30 to 15 meters with 100W