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A trifilar folded dipole antenna for 80 meters band

10 Meter Easy to build wire dipole antenna

Yagi-logper is a linux GPL program to model a Yagi or Log-periodic antennas with horizontal cylindrical dipoles.

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

A lightweight inverted vee antenna that can be supported by a 10 metre long fiberglass squid pole. The antenna is designed to cover 10, 15, 20, 40 and 80 m bands.

Basic information on the folded dipole antenna

A schematic antenna for a 40-80 Morgain dipole antenna with diagram and pictures, article partially in german

Over 1,000 stations in approximately 60 countries were worked using this modified twin-lead folded dipole, demonstrating its effectiveness with just 4 watts on 20 meters. This design, adapted from an ARRL Handbook concept, eliminates the shorting strap found in traditional folded dipoles, simplifying construction while maintaining performance. It utilizes readily available 300-ohm TV antenna feeder ribbon, making it a cost-effective solution for radio amateurs. The antenna's robust construction allows it to handle up to 100 watts without issues, even without a **balun**. The inclusion of a variable trimmer capacitor at the stub provides flexibility for tuning across different frequencies within a band, a practical feature for operators using transceivers like the Icom 735. Formulas are provided to calculate the precise dimensions for any desired operating frequency, enabling customization for various **HF bands**.

A balun is a MUST for dipoles or similar antennas when they are feed with coaxial cables. Many hams connect the center conductor of the coaxial cable to one side of the dipole, and the shield to the other. Wrong!

An Off-center-feed antenna that covers 80, 40, 20, 17, 15, 12, 10, and 6 meters

This article describes a project of asymmetrical hatted vertical dipole, a portable antenna that can be used for field day operations, sota, campings or even for fixed installations. This is a freestanding 20-10m antenna that is really easy to build, easy to tune and relatively easy to carry.

Homebrew a cobwebb antenna for the HF bands. This page describe a cobwebb multiband antenna resonating on 14 18 21 24 and 28 MHz. The cobweb antenna model can be considered a fan dipole, or better, multiple dipoles fed in parallel.

Inverted Vee antenna for 40m with simulation data by DF9CY

Article published on Practical Wireless about the W3DZZ multiband trapped dipole antenna made available by GM0ONX

Ham radio antennas and electronics, specialized in 1/2 wave dipole, OCF dipole, windom, full wave loop, end fed, inverted L, portable end fed antenna, long wire, SWL antenna, fan dipole, multiband dipole, G5RV and military antennas.

This 4m Slim Jim Antenna is cheap and easy to build yet it greatly out performs the more usual dipole due to its low angle of radiation. An SWR of 1:1 is obtainable across the 4m ham radio FM band with a simple adjustment.

This is an 80 metre dipole that fits in a small spac

How to operate on 10 and 20 meters in limited space with this trapped dipole.

The document provides a comprehensive overview of baluns, which are devices used to connect balanced loads, like dipole antennas, to unbalanced inputs, such as coaxial cables. It covers various types of baluns, including voltage and current baluns, and their design, construction, and testing. The text discusses the importance of baluns in preventing RF currents on coax shields and their applications in Ham radio setups. It also includes practical advice on selecting and using baluns based on antenna impedance and power ratings, along with detailed performance evaluations and construction tips for different balun configurations.

A short dipole wire antenna for 40 meters band. It is a folded dipole that do not make use of coils and can be used either in horizontal or inverted V configuration

A trapped dipole antenna based on the orignal W3DZZ antenna design resonating on 80 40 20 15 10 meters

A 40/80 meters dipole made with two loading coils based on a project by IK1ZOY

Although a magnetic loop antenna(aka small loop antenna) is very compact, its efficiency is close to a half-wavelength dipole if carefully built.

Construction details of a multiband dipole that can can operate at high power levels, and match its 50-ohm coax feedline without a tuner

This article explores the Cobra Junior linear loaded antenna for 80m to 10m bands. This antenna is a linear loaded dipole described by W4JOH in 73 magazine June 1997

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

A simple center-fed dipole made just with a thin-wall PVC pipe, aluminum tape, and RG-8X coax

A New Twist on Portable Multiband HF Dipoles, a Multi-band Spiral Dipole Off-Center-Feed match (OCF) antenna solution.

This document contains the detailed instructions to build a homemade lindenblad antenna using a twin-lead as dipole elements. This document contains 9 pages and includes a detailed construction sequence and some drawings to build this antenna for UHF and VHF ham radio bands

A folded dipole using twin lead By W8HDU

An homemade portable trapped dipole antenna for 40 and 80 meters band with an optional extension for the 20 meters.

A javascript online calculator for popular wire antennas, from the standard easy to build flat-top dipole, to the inverted V dipole, but also the Quad Loop, and the equilateral delta loop antenna

Centre fed half wave dipoles make great, simple and effective antennas for the HF bands. Sometimes however, the centre feed is not ideal. This great project will improve the overall antenna performance.

The Folded Dipole is not used much amongst Radio amateurs, probably due to the fact that this antenna uses twice as much wire as a single-wire dipole.

Extension to an existing fan dipole originally modeled for 40 20 and 6 meters. This modification will add 80 15 and 10 meter bands.

The GM4JMU Shortened 7Mhz Dipole

Multi-band loft-mounted dipoles for 40, 20, 17, 15, and 10m

The Fence Fan Dipole a quick, easy and inexpensive multiband dipole antenna

Just a basic dipole, under the edge of roof.

Interesting article on multiband fan dipoles. This article give an overview on designing this wire antenna, and planning a robust installation and proper feed line. Includes notes on setting up a commercial fan dipole antenna and on how diy your own.

A very basic guide to antennas concept. Explain the usage of dummy load, basic antennas like dipole o j-poles.

The Resonant Feedline Dipole (RFD) HF antenna design utilizes a single piece of coaxial cable and a stranded wire section, forming a 1/4-wavelength radiator. This configuration, based on a 1997 ARRL Handbook design (page 20.17), functions by RF traveling on the inside of the coax shield and returning on the outside, creating the second half of the dipole. A choke wound into the feedline prevents RF current from flowing back down the feedline. Construction details include using RG-58a/u coax for a 75m version, with a 1/4-wavelength section of stranded wire soldered to the center conductor. The document provides choke dimensions for RG-213, RG-8, and RG-58 coax across 3.5 MHz to 28 MHz, specifying cable length and number of turns. Dipole dimensions are also tabulated for frequencies from 3.6 MHz to 28.4 MHz, listing overall length and individual leg lengths. Field tests included deployment near Bryson City at 5 feet off the ground and as a sloper during WCARS Field Day in Asheville, yielding successful local and regional contacts.

An home made vertical dipole antenna made with simple material. The antenna has a total length of aproximately 16 feet. In this article appeared on June QST 2019, the author explain how he reached the optimal confirugation changing and adjusting the lower part of the antenna, trimming and spacing correctly the copper wire. PDF File to downloas

This short dipole antenna has been described by Nadisha, 4S7NR and may be of interest to anyone wishing to get on 80M (3.5MHz) that have limited space available.

A scanned PDF of this interesting book on HF Dipole antennas published by Stanford Research Institute

Homebrew a 2 meter square dipole antenna

A multiband vertical dipole antenna by ON4BAI

Unlocking the full multiband potential of the 225 Ohm elementary radiator in a folded monopole, dipole-like or turnstile layout, by Francesco Errante

An off centre fed dipole, with 10 feet of vertical radiator. It needs no tuner on 40m, 20m and 10m by M0UKD

17-Element Very High Frequency/Ultra High Frequency Log Period Dipole Array