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A simple VHF quarter wave antenna from PL25

A project for a vertical antenna for 60 to 20 meters by KV5R

An interesting presetnation full of usefull tricks to correctly design and build 23 cm Yagi using simple tools. The basic design of the antenna presented in this document is taken from the original DL6WU Yagi Design published in 1982

A simple kit for temporary, lightweight, wire tactical antenna systems is essential for any field Ops. Described in this article a kit as it fits in a standard US Military M-1956 Butt Pack

The Hexbeam is a great little antenna! It should be high on your list of options if you want a design that can be multi-banded, exhibits useful gain and directivity, is very lightweight, has a small turning radius, and which lends itself readily to Do It Yourself construction.

Aka Circular Waveguide Antenna. This online antenna calculator let you plan your cantenna for the desired frequency of operation, giving the Can diameter you have available.

Cheap but effective multiband quad antenna covering the entire horizon on 10-12-15-17-20m bands.

A simple and effective antenna launcher system by AA4LR

The problem originates by improper TXOUT-to-RF timing (RF transmission exists still after a TX-EN prohibition), combined by too long decay of their CW pulses.

This calculator calculates the length and width of a patch antenna based on the frequency, dielectric constant of the dielectric and the height of the thickness of the patch antenna substrate.

An homemade antenna tuner project that should be small, easy to build and cheap. This automatic antenna tuner can work as locale or as remote. The tuner has EEPROM memory for store settings for faster tunning and four interfaces

This home made antenna provides around 10.5dBd gain on 70cm, and 6.5dBd gain on 2m, which is more than adequate to work the FM satellites with a handheld dual band radio

Describes Atlantic Tower Services (ATS), a company specializing in antenna tower erection and maintenance, operating from Orlando, Florida. ATS offers a range of services including site maintenance, structural repairs, system modifications, and complete tower installations for various communication needs. The company emphasizes its capability to handle diverse tower projects, from routine inspections to complex upgrades, ensuring structural integrity and optimal performance for amateur radio and commercial installations. ATS focuses on delivering reliable infrastructure solutions, supporting the backbone of communication systems. Their service portfolio covers critical aspects of tower ownership, addressing both preventative care and reactive solutions for existing structures. They are equipped to manage projects involving different tower types and heights, adhering to safety standards and operational best practices. Services include **site maintenance** and _structural modifications_.

WD0M installation of the Hex Beam by SP7IDX

160 to 40 meters inverted L antennas projects

Inches and meters Javascript Wavelength Calculator allow to input a frequency in MHz and calculate wavelenght in several units considering also fractions of wavelenght and the velocity factor. Includes an usefull inch to meter converter

An overview of the basics of the horn antenna used in RF microwave applications.

SJ2W Contest Station, antenna for the 160 meter is a 39m vertical. This 160m antenna consist of 29m of WIBE tower sections with an insulated base and 10m top tube.

K1JJ presents a compilation of insights regarding vertical radial ground systems, specifically applied to 160m vertical arrays. The resource details 19 distinct observations and recommendations, emphasizing that ground radials primarily reduce ground losses rather than influencing pattern formation. It explains that RF current flows inefficiently through average soil, necessitating copper radials to create a low-resistance path back to the antenna base. The content suggests that **50-60 radials** are generally sufficient to achieve optimal efficiency, with diminishing returns beyond that number, and that radials should be laid on the surface for best performance. The discussion also addresses practical aspects such as wire gauge, installation techniques using 'U' shaped staples, and methods for connecting radials in multi-element arrays. It highlights the importance of radial length, stating that 1/4 wave radials are a crucial minimum, and that for 160m, radials should be at least _100 feet_ long. The resource critically examines the efficacy of elevated radials versus ground radials, noting that while a few elevated radials may suffice for VHF, HF applications, particularly on 160m, require extensive ground radial systems to efficiently collect RF currents in the near field. It also touches on the impact of radial systems on parasitic elements and the significance of symmetrical radial patterns for minimizing losses. Further practical advice includes wire type recommendations, proper soldering and weatherproofing techniques for radial connections, and considerations for integrating steel towers into the ground system. The author shares personal experience with installing 60 quarter-wave and half-wave radials under each of three in-line verticals, expressing satisfaction with the results.

A vertically-polarised VK2ABQ Antenna for six meter band

Summary, tutorial about the basics of what is a waveguide and the basic waveguide theory.

The AT-AUTO automatic antenna tuner handles 1.5kW CW operation, employing stepper motors under microprocessor control to precisely position a roller inductor and air-dielectric variable capacitor, avoiding relay-switched discrete components. This design choice prevents loud relay clacking and burning contacts, a common issue with competing products. The tuner features auto-retuning capabilities and receives periodic firmware updates, ensuring continuous improvement and added user-requested features. Its companion product, the _CX-AUTO_ coaxial switch, also features an embedded microprocessor controller. It enables selection of 1-of-8 coaxial outputs via a serial data interface. When integrated with the _AT-AUTO_, the tuner can associate specific coaxial outputs with amateur radio bands, automatically commanding the _CX-AUTO_ to select the correct antenna when the operator QSYs to a different band. Don Kessler began designing the AT-AUTO in 2005, with its debut at the 2006 Dayton Hamvention. Kessler Engineering also offers custom RF product design and electrical engineering consulting, specializing in Class-E RF amplifiers.

Antenna gain and directivity explained in this article at radio electronics antenna pages

An article about the Rybakov 806 Vertical antenna. The classic Rybakov configuration is a 7.6m or 8m ( aprox 25 or 26 feet) wire fed through a 4:1 UNUN

A page dedicated to servicing and building a 10 meter band moxon Antenna

A Yagi-Mag antenna for the 4 meters band with NEC and MMANA files plans and pictures

A VHF UHF antenna for the buddipole antenna system

Flag Antenna construction and test results by WA1ION

Article on Phase-cancellation of noise on 2m band

How to homemade antenna to be used with a handheld on the aircraft band to locate noise sources

Antenna design for Horn Antennas

Introduction to NVIS antenna and NVIS propagation. A simple NVIS antenna can be constructed as shown in this article

Tuning HF Coaxial Antenna Traps

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.

Ham Radio shop in Pray Montana offer a wide range of amateur radio, cb radio and two-way radio communications products

Comparison of some popular 432 MHz EME antennas by DF9CY

How to home made antenna traps with material you can easily find, and how to properly tune it.

Yaesu FT-100D Active Interface for the Codan 9350 and Comet SB-15 Antennas

It has been 40 years since the VHF-UHF Quagi antenna--a combination of the desirable features of a Yagi and a cubical quad--was developed and the design was first published in the newsletter of the Southern California VHF Club, a forerunner of today's Western States Weak Signal Society.

A simple dipole for 40m band feeded with 450-Ohm openwire feedline includes MMANA Gal files to download

A J-pole antenna plan for 50 MHz based on the DK7ZB design

Which is better a 20m antenna for an island DXpedition: Yagi at 25', or a vertical or two on the beach?

Building an omnidirectionnal antenna for the 23 cm band

The program consists of tabbed pages for various antenna and transmission line calculation. You can compute the values for an inverted L network that will allow you to match the 50 ohm output of the radio, or you can compute the necessary length in the units of choice for a 5/8 wave vertical for 10 meter band.

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

IZ5CML, Enrico Giannerini, obtained his amateur radio license in 1998, achieving DXCC contacts with all entities over 18 years of activity. His station, located in Empoli, Tuscany, Italy, focuses on HF and 50 MHz operations, primarily using SSB, CW, and some RTTY. He emphasizes direct radio communication, preferring "human modes" over digital modes like FT8/4, which he views as detaching the operator from the signal. Enrico's operating interests include DXing, IOTA activations, and major HF contests, where he has participated both individually and with teams like IQ5LV and IO5O. Notable activations include Sao Miguel and Flores (CU8, EU-089) in the Azores in 2005, and Antiparos and Paros (EU-067) in Greece in 2006 and 2014. He also contributes to the Hamradioweb forum, promoting good operating practices and publishing the monthly "Dxschedule" for upcoming DX and contest activities. The website includes a blog with articles on DX, ionospheric propagation, and antennas, reflecting his long-standing passion for radio, sparked by the 1980s film "La Tenda Rossa" and years as an SWL.

An article that explain with simple concepts and basic theory the correct usage of antenna tuners. It covers some aspects of common questions newcomers have on what antenna tuners are for, and what antenna tuners will never do.

An home made doblet antenna made with two Slinkys that are aproximately five meters in length connected with a twin-feed connected to a balanced ATU

Antenna Authority Inc. offers a wide assortment of directional, wideband antennas and other equipment specifically engineered for radio direction finding (DFing) and geolocation applications. Their product line includes _log periodic_, _cavity-backed spirals_, and _Yagi_ antennas, alongside covert antenna solutions for various operational requirements. The company emphasizes its expertise in designing and manufacturing specialized antennas for both overt and covert operations. Beyond standard offerings, Antenna Authority Inc. provides custom design services to meet specific client needs, focusing on tailored RF directional products. Their capabilities extend to developing antennas for vehicles and optimizing their operational performance in diverse scenarios. The firm is located at 3381 W. County Line Road, Douglasville, Ga. 30135-1145. Ferrel Bentley is associated with Antenna Authority Inc., which has been operating since at least 2005, as indicated by the copyright notice.

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.