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A presentation of the Yagi Antennas, and other interesting tid-bits by Brian Mileshosky. The document provides an in-depth exploration of the Yagi-Uda antenna, detailing its historical development, design principles, and performance characteristics. Originally described in the 1920s, the Yagi antenna features a driven element and parasitic elements, including reflectors and directors, which collectively determine its behavior. The document highlights how element lengths, diameters, and spacing influence gain, impedance, and directivity. It also discusses the antenna's reciprocal nature and presents data on typical gain values for various element configurations. Additionally, the text covers practical considerations, such as the construction of a "Tape Measure Yagi" for amateur use, and touches on related antenna types like dipoles and their application in Near Vertical Incident Skywave (NVIS) communication.

A distributed capacity coaxial dipole antenna. The antenna is very broadbanded with a very flat swr on all band when setup of the antenna is done at the proper lenght and height.

A bi-directional vertical antenna with 4db gain over a dipole.

An interesting presentation of a real multiband Fan Dipole antenna, optimized for better DX operation performances, considering the terrain, position, DX destination path and other influencing factors

Modeling the T2FD, tilted folded dipole antenna

Antennas are influenced by the effect of the ground and by the type of conductors from which they are constructed. Effects of various types of grounds on a 1.825 MHz horizontal 0.5 wave dipole

The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.

The page provides detailed information on a compact two-element yagi antenna, also known as the Moxon rectangle, specifically designed for the 17 meters band. It includes construction details, evolution history, performance data, and comparison with a 1/2 wave dipole antenna.

The VK5ABN loop antenna consists of a horizontal loop tuned to the 80M band and a dipole cut for the 30M band.

T2FD is a 600-900 ohms folded dipole, terminated with resistor. Feed impedance is coupled with 50/600 ohms voltage balun. It is a wide band antenna with rather low SWR over the full designed frequency range: antenna tuner is seldom needed.

W3HH wide-band wire antenna Article in French. The W3HH antenna, also known as the Terminated Folded Dipole (T2FD), is a compact, broadband antenna for amateur radio. It operates at an angle of 20 to 40 degrees and covers frequencies from 3 to 30 MHz. The antenna features a total length of one-third of the wavelength at its lowest frequency and is fed using a 1:4 BALUN transformer for impedance matching. A termination resistor around 390 Ω optimizes performance, making it suitable for various amateur radio applications while being easy to construct and install.

How complicated can a dipole be? Well, pretty complicated! Read on for details.

How to build Fan-Dipoles by DK7ZB. Experiences with various band combinations. Not all combinations are working properly. If the frequencies are to close together the impedances will lead to a very bad SWR. This happens with the bands 10-12-15m or 15-17-20m.

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

A simple drawing schematic of a portable field dipole for 14 MHz with dimensions in meters and instruction for setting up the antenna and to store the radial for easy transportation

This center-fed coaxial dipole for 4 mters feature low-cost components, Easy to set-up - nothing to adjust and no metalwork required, with only four soldered joints

This design has the following advantages low-cost components, Easy to set-up - nothing to adjust, no metalwork required, and only four soldered joints!

This article serves as a beginner-friendly guide to constructing a simple VHF dipole antenna for 2 meters, perfect for novices in the hobby. With an emphasis on affordability and simplicity, it explains the basics without overwhelming technical details. Recommendations for coaxial cable and mounting methods are provided, offering practical solutions for effective communication. By following these instructions, novices can build a functional antenna without breaking the bank.

An article describing a homemade 40m wire OCF Dipole

The radiating part is the vertical half of the dipole. You get nearly radiation in all directions, the second half must not be in 180°. The table below show how we get an impedance for direct feeding of 50Ohm coax. by DK7ZB

The antenna in this project is a modification of the techniques used to design a multiband fan type dipole with little or no tuning involved having a total space of 105 feet

As the name suggests, it is simply a dipole with the tips folded towards each other. In this case, a full-wave dipole. The span of a standard folded dipole is aprox 0,5 lambda. In this article the author investigate on differences between un-terminated vs terminated folded dipole antennas.

A very popular method of making a short dipoles resonate at a given frequency. This type of antenna is suitable for single band, narrow bandwidth use.

This LPDA calculator is based on the design procedure as described by L. B. Cebik, W4RNL (SK) in the 21st edition of The ARRL Antenna Handbook.

A VHF UHF antenna for the buddipole antenna system

A simple portable antenna for SOTA VHF is described in this article dedicated to portable operations

This variation of the basic horizontal, half wavelength flat top dipole has proven to be a simple, effective antenna suitable for both home and portable use.

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

One of the classic arguments in amateur radio is whether a dipole or vertical is the best antenna

Experimenting OCF and dipole wire antennas over house roof. Effects of roofs on wire antennas

Multiband Trap Dipole, portable short antennas, accessories and kits by DG1DBM

Comparing perfomances of two antennas using WSPR reporting system

A Six-element Yagi Beam for 6 Meter by W1JR proiddes a power gain of 10.2 dB over a dipole it is built on a 24 foot long boom

Complete collection of the four main parts of this excellet research on modelling and designing half wave dipole antennas for 40 meters band, covering all aspects beginning from full wave length antennas, to shortened, loaded and reshaped dipoles

Homebrewing a Lightweight linked dipole HF antenna for portable SOTA operations

Extending The Bandwidth of 80 Meter Dipoles

A dipole can be broadbanded by a number of techniques including by matching with resonant sections of transmission feed lines.

A multiband Fan Dipole that works on 40 20 15 meters band, making a folded dipole for 7 MHz band and additional element for the 21 MHz and 14 MHz

The folded dipole antenna or folded dipole aerial is widely used, not only on its own, but also as the driven element in other antennas like the Yagi antenna and various other types of antenna. Folded Dipole Myths, Bandwidth and details on folded dipoles

In this article, author examine stresses placed on common-mode chokes (aka baluns) as hams use/abuse them, examine the efficiency of simple dipole multi- band antennas and their feed systems. Stressing a Balun.

An antenna for 80 meters band for those who does not have enough space to setup a halwave wire dipole that is aprox 130ft or 40 meters. The antenna is an open-wire-fed shortened dipole

An inverted V Dipole antenna for HF bands, working on 10 20 40 and 80 meters band. PDF Presentation

Experimenting a 20 40 meter short coil loaded dipole antenna with the goal to keep the total length under 40 feet so that the dipole can be mounted on two 20 foot fiberglass pole to make a 20/40 meter rotatable dipole.

A dual band dipole antenna for 40 and 80 meters band. Total lenght of 26 meters, foreseen two coils at aprox 11 meters distance from center feed.

Full article on how to build a home-made wire dipole antenna for 40 and 80 meters band. Article is fully in italian, as it was published on ARI RadioRivista, but is plenty of self explaining pictures that will guide you on homebrewing this trapped dipole antenna for the lower amateur radio bands.

Roach pole vertical antenna for 40 and 30 meters band featuring good performance on short skips contacts compared to wire dipole

Basic dipole antennas by KN9B

An experimental prototype of an asymmetrical hatted vertical dipole antenna that can work on HF bands 20 to 10 meters band. The AHVD Vertical dipole is an upside-down T design

STAR-H Corporation specializes in extremely wideband dipoles and compact low-profile antenna systems for military, emergency management, commercial operations and consumer wireless applications.

The 2.6 Mhz M Dipole is constructed from #10 stranded insulated wire available in most hardware stores. The feedpoint uses a T-section of PVC pipe