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CG Antenna is a HF radio communication solution manufactory based in China produce automatic antenna tuners, and digital radio interfaces.

Homebrewing a Gamma Match to tune yagi antennas

Super Antenna Systems for HF - VHF - UHF Portable Stealth Mobile Base Backpack EmComm Ham Radio antennas

This is a presentation used at OVARC on the LindenBlad antenna construction. The presentation cover several topics about this antenna, from the basic antenna design, to the guide on how to contruct a custom lindenblad antenna for the 2 meters band and and 70 centimenters band.

Wheel antenna informations by The Olde Antenna Lab

There are a large number of antenna designs for HF. One choice out of many is the fan dipole. The ability to transmit of multiple bands without needing a tuner (and even more with a tuner) is a very desirable factor in choosing a versitle antenna for HF.

Dipoles at the correct height are not only stealthy antennas, they work great

Experimenting vertical wire antennas for 40 and 20 meters supported by balloons resulting in excellent gain in RX and good overall performance against horizontal dipole

This is about Small Antenna types and their properties which can help choosing proper antenna for high-frequency wireless communications as: two-way radio, microwave short links, repeaters, radio beacons or wireless telemetry

The N3UJJ antenna project,parallel-cage dipole a multi-band horizontal antenna, without the need of an antenna tuner.

Theory and origins of W4RNL Asymmetrical Hatted Vertical Dipole AHVD for portable operations.

Assembling installing and tuning the Butternut HF9V multiband vertical antenna

The 60-page PDF document, "Antenna Systems and Theory For The Non-Technical Ham" by Jim Abercrombie, N4JA, provides a foundational understanding of antenna systems. It explains basic antenna theory, including how antennas work, electromagnetic wave polarization, and the role of frequency. The resource details various antenna types such as flat top dipoles, inverted-V dipoles, shortened loaded dipoles, G5RV dipoles, Carolina Windoms, and end-fed configurations. Vertical antennas, including ground-mounted trapped verticals and inverted-L verticals, are also covered. Directional beam antennas like monoband Yagis, cubical quads, and log-periodic arrays are discussed. Propagation modes, including ground-wave, direct wave, and skywave propagation, are explained in detail, with specific attention to the D, E, and F layers of the ionosphere and their effects on HF communication. Technical concepts such as standing wave ratio, decibels, resistance, and reactance are defined, along with calculations for half-wave resonant dipole lengths. The document addresses feed-line radiation, balun applications, and critical antenna and tower safety considerations. It aims to dispel common antenna myths and educate hams on making informed antenna choices.

NVIS antennas, also known as Near Incident Vertical Skywave antennas have a high angle of radiation. Something on the order of 60 degrees, to straight up to 90 degrees. A portable, easy to setup and cheap nvis antenna project.

An EH Antenna for 14 MHz by EB3EMD based on an original project by F5SWN

An economical dipole for simple QRP HF homebrew rigs

cq-contest reflector comments about the performance of the EWE receive antennna collected by KA9FOX

Manufacturing selling and supporting the classic W7FG True Ladder Line Wire and Antenna

Hexbeam antenna project for 20, 15 and 10 mtrs

During a club's "Filetto Day" event, a comparative field test was conducted between a **Buddipole** antenna and a homemade 20/40-meter wire dipole. The author, IW5EDI, performed this personal evaluation from a mountain top at 1500 meters above sea level, utilizing a Yaesu FT-857D transceiver to switch between antennas. The observations on the 20-meter band indicated that the wire dipole consistently delivered significantly stronger signals compared to the Buddipole. Additionally, the Buddipole exhibited higher levels of **QRM** during the listening tests. The commercial Buddipole, known for its multiband capability and compact size with a self-supporting tripod, was contrasted with the simpler, larger wire dipole, which required a fiberglass fish pole for support. This direct comparison highlights practical differences in performance and deployment between a popular portable commercial antenna and a basic wire antenna in a real-world operating environment.

US amateur radio antenna manufacturer, design and build monoband, dual band and multiband Yagi Antennas for HF bands as well as receive antenna systems

A frame antenna for the 80 meters band, built to be folded and to be easy to be mounted and dismounted. This antenna is suitable for indoor and QRP use, bandwidth is just 10kHz and should be observed a proper distance while transmitting due to high voltage.

Want to operate on 40 meters but only have a space a little over 16X16 ? Try this antenna.

Amateur radio antennas manufacturer, produce multiband and monoband high performance yagi antennas and vertical antennas based in Poland

A long picture gallery of a homebrew hexbeam antenna project

The collinear antenna, or Marconi-Franklin antenna, is an omnidirectional, high-gain antenna composed of in-phase half-wave dipoles aligned vertically. By using quarter-wave transmission line segments, it maximizes gain at a low horizon angle, outperforming a half-wave dipole. Adding segments increases gain but narrows bandwidth. A popular DIY version, the CoCo antenna, uses half-wave coaxial cable segments connected by non-radiating transmission lines. Built with stable velocity factor cables, a matching quarter-wave sleeve balun, and ferrite rings for attenuation, the antenna achieves performance comparable to commercial models.

Introduction to Shortwave Antennas. Understanding Shortwave Radio Listening and Antenna Design and Construction

The 9W2VVH blog documents the amateur radio journey of Hussairy, focusing on his station setup and operational experiences from Malaysia. Content includes details about his _Yaesu FT-857D_ transceiver, which serves as the primary rig for HF, VHF, and UHF operations, often paired with a _G5RV_ antenna for HF bands. The site also features discussions on various aspects of ham radio, such as antenna experimentation and QSL card exchanges, reflecting a hands-on approach to the hobby. Operational updates frequently cover DX contacts and local ragchews, providing insights into propagation conditions and operating techniques from Southeast Asia. The blog serves as a personal log and sharing platform, showcasing the practical application of amateur radio equipment and fostering connections within the global ham community.

ZL1BJQ 23 feet diameter dish antenna for 432 Mhz

Amateur Radio 40m 20m 15m Half Wave Fan dipole antenna project with part list, pictures and drawing. Includes the option to expand the antenna to cover the 80 meters band

Ham Radio Vertical HF multiband antennas manufacturers based in Spain

Mounting antenna close each other. Distance calculations and tips on setting up antennas by KB9VBR

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

21 28 and 50MHz three bands whip antenna by JA1HWO

Design and build a 6 meter 2-element Moxon antenna mostly from available aluminum tubing and angle stock.

Using Andrew FSJ1-50A 1/4" Superflex Heliax with PL-259 Connectors

A quarter wave antenna with dimensions for uhf and vhf bands

A page descibing the principles of OCF antennas also known as windom antennas by DJ0IP

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

This method of construction can be used on most UHF through \"low\" microwave Yagis, and is especially useful for the 33, 23 and 13 cm bands

Home made wire dipole on a lenght of 30 meter 98.4 ft by PE1OPM

Cheap and light portable 2m Yagi

A collection of drawings of most popular wire antennas for hf ham radio bands

6m/2m/70cm Yagi Antenna Built from Old TV Antenna This turned out to be a great little antenna. It works the 6 meter, 2 meter and 70 centimeter bands. You can use one common feedpoint or two seperate feedpoints depending on how you would like to connect this antenna to your transceiver.

The Icom AH-4 autotuner operates efficiently across multiple HF bands, providing seamless automatic tuning for antennas from 3.5 MHz to 54 MHz. Its robust design allows for outdoor installation, making it suitable for field operations and fixed stations. The unit interfaces with Icom transceivers via a control cable, enabling automatic band switching and tuning. The AH-4 is capable of handling up to 120 watts of RF power, ensuring compatibility with most amateur radio setups. Its weather-resistant casing and compact form factor make it a versatile choice for operators requiring reliable performance in diverse environments. Field tests demonstrate the AH-4's ability to maintain low SWR across its operational range, enhancing signal quality and transmission efficiency. Compared to manual tuners, the AH-4 offers significant time savings and ease of use, particularly in rapidly changing band conditions. Its integration with Icom radios simplifies operation, eliminating the need for manual adjustments. The autotuner's performance is consistent with other high-end models, providing a cost-effective solution for amateur operators seeking dependable tuning capabilities without sacrificing performance.

Constructing a 2-meter Moxon antenna for MURS channels, this resource details the antenna's geometry and expected radiation pattern. The design, optimized for low SWR, high gain, and front-to-back ratio on the first three MURS channels, uses 1/8-inch bronze brazing rod for elements. Author John E. Davis provides specific geometric parameters (A, B, C, D dimensions) rounded to the nearest 16th of an inch, along with a link to the final _.nec_ file for further analysis. Performance results show the attic-mounted Moxon performs well on the 2-meter band, despite its MURS optimization, with measured SWR plots provided. NEC-2 modeling predicts over 6 dBi gain and 40 dBi front-to-back ratio in free space. The author compares its directional performance to a _J-pole_ antenna, demonstrating substantially better signal strength for a nearby repeater when the Moxon is pointed in its general direction, confirming its superior gain and directivity.

Presents Eagle Stainless Tube & Fabrication as a certified distributor specializing in various tubing products essential for antenna construction and other amateur radio projects. It details their offerings, which include aluminum tubes in fractional, metric, and heavy wall specifications, alongside stainless steel bar stock in round, square, and flat profiles. The resource highlights the availability of a diameter sizing chart and direct contact options for specialists, indicating a focus on providing specific material dimensions and expert support for custom fabrication needs. The company emphasizes its role as a supplier of raw materials, crucial for hams engaged in DIY antenna builds or structural components for their shacks. Their inventory supports the precise mechanical requirements often encountered in radio frequency engineering, where material strength, weight, and corrosion resistance are critical design factors for outdoor installations. The site primarily serves as a product catalog and contact point for sourcing specialized metal tubing and bar stock, providing technical specifications and material grades relevant to robust amateur radio infrastructure.

A vehicle mounted portable antenna mast.

Amateur, scanner, wi-fi and land mobile antennas and accessories online store

Optimizing weak signal reception on the HF bands, particularly in the presence of strong local QRM, often necessitates specialized receiving antenna systems. This resource details the _HI-Z Antennas_ product line, focusing on phased vertical arrays designed for superior noise rejection and directivity. It covers components such as the 4-Square and 8-Element array controllers, which allow for rapid switching of receive patterns, and dedicated low-noise preamplifiers to improve system sensitivity. The site also presents various bandpass filters, crucial for mitigating out-of-band interference and enhancing the dynamic range of the receiver. The HI-Z systems are engineered to provide significant front-to-back and side rejection, often yielding **20-30 dB** of attenuation to unwanted signals, which is critical for DXing and contesting. Users can achieve a notable reduction in local noise, allowing for the discernment of signals that would otherwise be buried. The array controllers facilitate quick pattern changes, enabling operators to null out interference or peak weak signals from distant stations, effectively extending the reach of their receive capabilities by improving the signal-to-noise ratio.