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The QM7 antenna is a simple 7 elements Yagi with 3.70 m boom length for the lower 144 MHz SSB/MGM band, used it mainly for Sporadic-E and MS contacts. It exhibits a forward gain of 11.35 dBd; i.e. 13.5 dB forward gain over the isotropic radiator, while the F/R is about 12.5 dB

A rotary trapped-dipole for 17 and 20 meters, as described by IZ7ATH, presents a practical solution for multi-band HF operation. The author, Talino, recounts his experience building this antenna for IK7ZCQ, detailing the evolution from an initial concept involving a grounded-driven element and gamma-match to a direct-fed, non-grounded design. His pragmatic approach, adapting available materials, is evident throughout the construction narrative, particularly with the use of eight tapered aluminum pipes for the driven element. Construction specifics include precise measurements for the aluminum tubing, with diameters ranging from 30 mm down to 16 mm, and a critical note on reducing tip thickness for weight optimization. The _traps_, initially a concern, are fabricated using 8 turns of RG58 coax on a 27 mm support, tuned to resonate at 18.1 MHz using a dip-meter. Talino emphasizes sealing the traps with RF glue and PVC tape to prevent water ingress, a crucial step for longevity. Field test results, conducted on a 10-meter pole in a clear garden environment, showed an SWR of 1.2:1 on 17 meters and 1.5:1 at 14.200 MHz. While SWR varied slightly when installed at Mario's QTH due to nearby objects, the antenna's performance remained commendable. The final half-dipole length is 46 cm for the 18 MHz tips, and the total weight is under 6 kg, with potential for further reduction.

An AO-10 antenna by K5OE, this design is optimized for 436.8 mHz with a 50 Ohm feed

This is a C-L-C type tuner with a reflected power indicator. Tuning is done for minimum reflected power.

Ham Radio Antenna Tuners--Full Legal Power--Patented Circuit--Outstanding Efficiency and Power Capability

The W8JK is a famous and effective DX antenna, first built by John Kraus, W8JK, in 1937. A Beam antenna with two parallel dipoles driven with opposite phase, with a close spacing of an eighth of a wavelength.

HF/6M antenna tuner preselector and antenna switcher project by ON6MU

Article on building a folded bazooka antenna

Build parabolic WLAN antenna adapted from a small satellite dish. It provides high gain and long range connections.

A free online calculator for making all of the calculations required to design and build small transmitting loop antennas, also known as magnetic loops by 66pacific.com

Theory and operantions, G5RV construction tips by Keith, KE2DI

French manufacturer (F5MSU) of antennas and accessories since 1999 : Yagi, Delta-loop, dipoles, T2FD, verticales, EFHW, baluns, ununs, etc.

Kv5r Understanding NVIS Antennas and Propagation. This article is not intended to be a complete primer on HF radio propagation or emergency communications.

Tarheel Antennas presents its product line of motorized **screwdriver antennas** and stainless steel mounting solutions, engineered for both amateur radio operators and commercial users. The resource details the manufacturing process, emphasizing in-house CNC machining and the use of quality materials for durability and performance. It highlights the company's commitment to U.S.-based manufacturing, with products built in St. Joseph, MO, since 2008. The site provides essential contact information for sales and technical support, including email addresses and phone numbers. It also includes a mailing address for physical correspondence. While noting a temporary absence from the Dayton Hamvention in 2024, the company expresses intent to return in 2026, indicating engagement with the amateur radio community.

G8ODE 160 m Top Band Inverted L Antenna made of 33m horizontal wire in the garden

A 3 and 5 element portable yagi antennas for 2 meter band

An horizontal full wave wire loop antenna for the 80 meters band by W4HM

HF Antennas, magnetic loop antenna, based in Italy

HA2NON W3DZZ antenna project with pictures and construction details

Mobile Antennas, mini magnet antennas, handheld antennas, by Reuex industrial

Constructing a **2-meter** J-pole antenna from readily available copper plumbing components offers a robust and cost-effective solution for VHF operation. This design, dubbed the "Plumber's Delight," functions essentially as a half-wave dipole fed by 50-ohm coax via a **gamma match**. It incorporates a quarter-wave copper tubing support, which, when affixed to a metal mast or tower, enhances forward power in the direction of the radiating elements. The original configuration utilized a small ceramic trimmer capacitor for the gamma match, suitable for up to 10 watts. A subsequent modification replaced this with a 50 pF variable capacitor housed in a plastic enclosure, accommodating higher RF power and improving weather resistance. The antenna elements are secured using a copper "T" fitting, and an SO-239 connector mounts directly to this fitting. Performance includes gain away from the support mast, and tuning is straightforward by adjusting the gamma match capacitor for a 1:1 SWR. The total cost for materials, excluding the capacitor and coax, can be under $10.

Presents G0GSF Brian's ZS6BKW antenna, a refined iteration of the classic G5RV, offering improved performance across multiple HF bands. The design emphasizes specific radiator and ladder line lengths to achieve lower SWR on 40m, 20m, 17m, 12m, and 10m, making it a practical choice for operators seeking a single wire antenna solution. The document includes critical dimensions for the flat-top and the 450-ohm ladder line section, which are key to its multiband resonance characteristics. Unlike the original G5RV, the ZS6BKW aims for direct 50-ohm feedpoint impedance on several bands, reducing the need for an external antenna tuner. My field experience with similar optimized dipoles confirms that precise construction, particularly the ladder line length, is paramount for realizing the intended SWR benefits. This design offers a compelling alternative for hams with limited space or those preferring a less complex antenna system.

U.S. Marine Corps in PDF format

These omnidirectional antennas offer Horizontal polarization, and about 2.1 dbd of gain. They are much quieter than a dipole or a vertical, have a broader bandwidth and will usually out perform a dipole antenna.

Based on a W4TWW project and modified by KN4LF

The page provides detailed instructions on how to build a double bazooka antenna for the 40 meters band. It includes information on materials needed, measurements, and assembly steps. The antenna can be configured as an extended dipole or an inverted V, offering low noise, wide bandwidth, and a 1:1 standing wave ratio. The content also offers calculations for other bands and includes photos of the antenna fabrication process.

If you have ever tried transmitting on HF from a tall block of apartments, where it's just not possible to erect a substantial aerial system, then this article is for you

This project describes an ARDUINO based automatic antenna tuner, for an end-fed half wave (EFHW) antenna, working on 20 & 40 meter bands

A Bencher antenna divsion, manufacturer of HF YAGI and Vertical antennas

design note by Brian Williams, GW0GHF

A pedestrian antenna is considered to be a lightweight antenna that can easily be carried to the shootout by one person in a backpack or bag.

Log periodic antenna design excel sheet file download, in italian.

A Quad Fractal Antenna for 20 meters band by F3DD

This project is about a cheap way of building a colinear antenna for VHF 145MHz, and having about 10dB more gain than that little 1/4-wave magmount

A 2-meter Turnstile antenna, detailed for amateur satellite communication, offers a straightforward build for those looking to engage with orbiting transponders. The author, WB8ERJ, shares his personal design and construction methods, emphasizing the antenna's simplicity and effectiveness for LEO (Low Earth Orbit) satellite work. This design provides a circularly polarized signal, crucial for mitigating _Faraday rotation_ and signal fading often encountered with linearly polarized antennas when tracking satellites. Construction involves readily available materials like PVC pipe and copper wire, making it an accessible project for many hams. The article includes practical advice on element spacing and feed point considerations, drawing from the author's hands-on experience in the shack and field. It highlights the antenna's utility for receiving signals from various amateur satellites, including the popular AO-91 and AO-92. The Turnstile's inherent omnidirectional pattern in the horizontal plane, combined with its circular polarization, yields consistent signal reception, often resulting in **stronger decodes** and **more reliable contacts** compared to basic dipoles or verticals.

Rhombic Antenna dimensions for HF and VHF bands by N6JSX

A simple T-network that can match any unbalanced antenna system by AA5TB

SuperAntenna offer Portable, Stealth, Mobile, Base, Backpack, EmComm, Ham Radio, Marine, MARS, CAP, HF SSB, Gov, NGO and Commercial antennas

The BV6 50 MHz Yagis resource details the construction of two distinct Yagi antenna designs for the 6-meter band, specifically a 1-wavelength (1wl) model and a 2.1-wavelength (2.1wl) model. The 1wl Yagi, with a boom length of 5.850m, achieves a gain of **9.4 dBd**, while the 2.1wl Yagi, spanning 12.90m, boasts a gain of **11.9 dBd**. These designs adhere to a proven methodology for optimizing current slope and maintaining constant phase delay across parasitic elements, ensuring high gain per boom length and an _excellent pattern_. Both designs target a 50-ohm input impedance, facilitating straightforward feeding with a robust folded dipole. Final verification using NEC-II software confirmed the antennas' exceptional stacking capabilities, yielding stacking gains exceeding **5.8 dB** for a 2x2 array with minimal mutual detuning. The resource provides common mechanical data, including boom and element diameters, and specifies element lengths corrected for boom diameter. While the original _DUBUS Technik V_ publication contained incorrect element lengths, this resource provides the accurate dimensions for proper construction, emphasizing the use of readily available materials for cost-effective amateur radio deployment.

Amateur quarter wave ground plane antenna calculator, calculate vertical and radial length

This Field Day Vertical Antenna project is the result of many years of attending various field day sites and realizing that what was needed is a simple, easy to assemble vertical antenna.

The terminated tilted, folded dipole T2FD is a little known antenna that performs excellently. Compact in size compared to a half-wave dipole the T2FD provides signal gain, wide frequency coverage, and exceptionally low noise characteristics.

These devices are called Traps, but they are actually more like frequency sensitive switches. They are parallel resonant, high Q, tuned circuits which provide a very high impedance at their frequency of resonance.

Calculate your dipole, 3 element yagi and a simple dipole

The IK-STIC 2 is a vertical, all band, antenna that is over 25 feet tall yet weighs under 5 pounds. Based on a telescopic pipe or a fiberglass fishing pole, using a tuner it can easily cover the amateur radio HF bands from 40 - 10 Meters

What type of antenna should I get? Well, the best type of antenna for working the OSCAR satellites are circular polarized antennas

The K4VX linear-loaded dipole for 7 MHz, simple and practical way to make a short but efficient 40-meter dipole.

VE7CA reprint an interesting article taken from arrl antenna compendium. Two elegant practical and portable 6-meter gain antennas, a two-element quad and a tree-element Yagi antenna for 50 Mhz-6 meter band

Why a vertical antenna or longwire antenna might require a balun

the multiband Notebook Antenna, so called because the entire antenna will fit easily inside a 1" thick 3-ring binder