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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 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.

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

This web article details the construction of a 4-meter band coaxial dipole antenna, designed for operation between **70.000 MHz and 70.500 MHz**. The resource provides a bill of materials and step-by-step assembly instructions for a half-wave dipole constructed from _RG-58_ coaxial cable. The design specifies a direct 50 ohm feedpoint impedance, eliminating the need for an external matching network. Construction photographs illustrate the stripping and soldering processes for the coaxial cable elements, ensuring proper electrical connection and physical integrity. The article includes specific dimensions for the radiating elements, derived from calculations for the 70 MHz band. The project outlines the physical dimensions required for resonance at 70 MHz, with the outer braid forming one half and the inner conductor forming the other. The feedline connection is directly to the coaxial dipole's center, maintaining a 50 ohm characteristic impedance. While the article does not present SWR plots or VNA sweeps, it focuses on the mechanical construction and dimensional accuracy for achieving a functional 4-meter dipole. The design is intended for fixed station use, with no specific mention of polarization or height above ground, but implies a standard horizontal orientation for dipole operation. DXZone Focus: Web Article | 4m Coaxial Dipole | Construction Guide | 50 ohm Feed

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

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 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.

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

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

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

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

Extending The Bandwidth of 80 Meter Dipoles

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

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.

Maxcon makes and sells Amateur Radio Antennas. Double extended Zepp antenna, multiband dipoles, bazooka antennas, and VHF Jpole, made in USA

QRSS operations on 30M with an home made dipole

RSGB article for beginners. How to build a dipole antenna, construction tips and correct setup of inverted-ve dipole antennas

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.

Diamond W8010 Multiband Dipole Modifications

A folded dipole is an antenna, with two conductors connected on both sides, and folded to form a cylindrical closed shape, to which feed is given at the center.

A trap antenna dipole covering two differen bands made reusing an old 160/80m inverted vee antenna.

Antenna may be made practically from any wire (strand, solid) having a reasonable diameter 0.5 2.0 mm (24- 12 AWG). Antenna may be installed at any balcony of 3 to 6 meter length.

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

Measuring noise fiugre on the W2IMU horn and the dual-dipole-feed

This is a standard calculation method that can help you while tuning dipole antennas, by adjusting wire lengths. This method can be used also when you need to add lenght to your wires, and can be additionally used to quarter waves vertical antennas

A fand dipole antenna home made for the 7,14,50 MHz. This article descbribes how to homebrew the antenna, hot to setup and some SWR measurements.

This DIY vertical multi-band Windom antenna offers a practical and effective solution for amateur radio enthusiasts seeking a versatile and compact antenna for HF communications. Its simplicity of construction, multi-band capability, and favorable performance make it a valuable addition to any radio shack. The article provides detailed instructions on constructing the antenna and balun, along with diagrams and component specifications. Field tests demonstrated successful contacts with stations across Europe and North America on 14, 18, and 28 MHz. The antenna exhibited comparable performance to a W3DZZ dipole and outperformed a Cobweb antenna on 18 MHz. Low noise levels were observed, effectively suppressing background noise.

The OCFD Off-Center-Fed Dipole Antenna is an excellent multiband antenna that is relatively simple to construct, yet gets quite decent performance.

This antenna is an off-center fed spiral dipole for 40 meters. The spiral dipole is very compact, making it well-suited for limited space (like an apartment patio), while the off-center feed gives the antenna some multiband capability.

A simple portable dipole antenna for the 40 meter band using a total lenght of 18 meter. It can be used for 80 to 10 meters coverage using a antenna tuner.

How to setup and configure the buddipole antenna in the J-Pole mode for the six meter band

A portable home made wire dipole antenna that works on 40 30 and 17 meters band.