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

A DIY project of a WiFi 10 elements Yagi antenna

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

A method for supporting a balun on a Chushcraft A3S antenna. This allows the balun to be isolated from the boom, thus reducing the effect of introduction of reaction with the balun core.

A 4 elements handitenna for 70 cm band. This is my version of the K5OE Handitenna. This one is a four Element instead of three, as I had less of a crunch on space than he did. The 1st three elements (Reflector, Driven Element, and Director 1) are the same dimensions as his were.

Notes on W3EDP Antenna by M1KTA

An end fed 20 meter half wave antenna

The resource details the construction of a **Hustler-compatible** HF mobile antenna mast, utilizing 1/2-inch copper water pipe and common hardware. It provides a bill of materials, specifying one 10-foot copper pipe, four 1/2-inch copper end caps, and 3/8-inch fine-thread hex bolts and nuts, totaling $8.75 for two masts. The construction process outlines preparing bolts by rounding their heads, drilling 3/8-inch holes in end caps, soldering bolts into caps, and then soldering these cap/bolt assemblies to 5-foot sections of copper pipe to achieve a final length of 54-1/4 inches per mast. The method emphasizes precise soldering techniques to ensure structural integrity and proper fit. The resulting masts are presented as functional alternatives to commercial units, with the author noting their performance is comparable to the "real thing." Installation tips are provided, including the use of braces connected to a trunk lid to mitigate stress on the antenna mount, contrasting this approach with WA8WTE's spring-based method. Photos illustrate the completed mast mounted on a vehicle, demonstrating practical application and support strategies for mobile HF operation, particularly with larger coils and longer whips at highway speeds.

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.

This article describes a simple Inverted L antenna for the HF bands designed to work on 80m, 40m, 30m and 20m

VHF UHF diplexer by G8MNY

Presents the construction of a 6-meter (50 MHz) Moxon wire beam antenna, detailing the use of #14 AWG THNN stranded wire and a treated wood frame. It covers the assembly of a galvanized pipe mast, emphasizing the use of pipe sleeves for joint reinforcement over threaded couplers to prevent breakage during raising and lowering operations. The resource also describes the integration of a 1:1 current balun, rated for 50-54 MHz, and the use of RG-8X coax for the transmission line, recommending low-loss alternatives like Belden 9913-7F. Further, it outlines a manual rotation mechanism using pipe hanger clamps and carriage bolts for true North orientation, incorporating magnetic declination calculations from NOAA. The antenna's performance is discussed, noting good gain and take-off angle, with SWR tuning facilitated by a Palstar AT-500 manual tuner. An EZNEC+ 5.054 model for the antenna is available for download, alongside predicted radiation patterns and SWR curves, compared with actual AIM-4170C measurements.

Basic of shortwave antennas

Open-Wire/Twinlead Antenna Switch

Ferrite rod antenna or aerial, a form of RF antenna that is widely used in RFID and transistor radio applications.

A 70cm and 2m 6 elements yagi antenna plan based on the IEEE Transactions on Antennas and Propagation

a methodology for connecting multiple LF/MF/HF receivers to a single antenna via readily available and inexpensive 75-ohm TV cable.

A Useful Horizontally Polarised Omni-directional Antenna with Gain for 144 MHz

Comparison of 50 and 70 Mhz antennas, commercial and home made projects

An easy portable VHF antenna to build for ARES - RACES work is the 300 Ohm Twin Lead JPole antenna

This is the Loop Antenna Group to Ask Your Questions, Get Answers and Information about Loop Antennas for improved your Radio Listening and Enjoyment.

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.

Demonstrates the construction of a _3MA triband mobile antenna_ designed by IZ7DJR, emphasizing a full-size quarter-wave whip for 10 meters. The design incorporates a rapid tilt-down mechanism to facilitate quick changes of loading coils for operation on 15 and 20 meters. This approach aims to minimize losses and enhance efficiency compared to conventional base-loaded mobile antennas. The resource provides specific coil winding data: 22 turns for 15 meters and **37 turns** for 20 meters, both using 1mm wire over an 80mm coil length. The 10-meter band operates without a loading coil, leveraging its full-size design. The author's design prioritizes ease of band switching and improved performance for mobile HF operations, offering a practical alternative to more lossy commercial options.

A homebrew Magmount for 2m antenna

This antenna analyzer measures complex impedance over the 1.6 - 33 MHz HF spectrum

A Slinky-based doublet or loaded vertical QRP antenna tested for 40 meters band

An easy to deploy antenna, commonly considered the best solution for portable operations. Thir article includes a simple LC parallel circuit to match the impedance by IW7EHC

Pneumatic Antenna Launchers for sale

2 Meter Indoor Slim Jim Antennas for Cyclone Season and Other Uses by VK4MDX

This article explores the performance of an unloaded elevated vertical, base matching and feed line as a multi-band HF antenna system.

This article describes the characteristics of the Windom antenna and shows the results of several simulations made with MMANA-GAL, covering models optimized for the 20 m, 40 m and 80 m bands.

A compact antenna for 160 meters, suitable for hams tha want operate top band buh have a limited space

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

A radio's transmitting power can be concentrated along the horizon by use of a GAIN antenna. Although you may still be transmitting with four watts of power, your effective radiated powerwill be greatly increased. This table shows the effects of antenna gain on a transmitter with 4 watts of transmit power.

Helix antenna design and construction details

A 5 band two element quad antenna working from 20 to 10 meters using hardware-store parts or modifying an existing commercial triband quad by KC6T

Detection and recording of Schumann resonances and other electromagnetic phenomena at frequencies below 50 Hz By Hans Michlmayr

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.

W3EDP antenna assembly instructions and dimensions with pictures in this PDF File

The basics of what is a discone antenna for wide band or bandwidth omnidirectional applications.

This article explores the performance of an unloaded vertical as a multi-band HF antenna.

Analysis of an antenna trap where a coil is formed of a length of coax cable, the outer conductor of one coax end is tied to the inner conductor of the other coax end, and the remaining connections form the terminals for the trap.

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

Optimizing a G5RV or ZS6BKW multiband wire antenna for HF operation often involves addressing common SWR issues and understanding feedline characteristics. This resource chronicles the construction and performance evaluation of a G5RV, initially built for 80m, 40m, 15m, and 10m bands, by a newly licensed Foundation operator. The author details the selection of materials, including 3.5 mm stainless steel wire for the doublet arms and enameled copper wire for the open-wire feeder, and the initial decision to omit a balun based on common online information. The narrative highlights the initial disappointing performance, characterized by high receive noise and poor signal reports on 80 meters, despite the transceiver's internal ATU achieving a 1:1 match. This led to experimentation with a coax current balun and further research into G5RV myths, such as SWR claims and the necessity of a balun. The author then describes modifying the antenna to the ZS6BKW configuration, which involves specific changes to the doublet and feedline lengths, and integrating a 1:1 current balun wound on a ferrite toroid. The modifications resulted in improved reception and transmit performance across the bands.

A loop antenna made with common RG-213 coax and rests on a cross made of 6 mm fibreglass rods anf a 6.5- 30MHz tune

An interesting article on random wire antennas, and how to choose the optimal lenghts for multiband operations.

A four element 2 meter quad antenna project

A vector graphic antenna analyzer project page by DC2WK demonstrating a project realized by DG7EAO includes, part list, schematics, and videos.

The resource details the construction of a 3-element Yagi antenna specifically designed for the 6-meter band, providing coverage across 50-54 MHz. This antenna design, originally featured in _QST_ August 2007, emphasizes a short boom configuration while maintaining a wideband response. Key specifications include a 50 Ohm SWR of less than 2:1 across the entire band, achieved through specific element lengths and spacing. The design utilizes aluminum tubing for elements and boom, with detailed dimensions provided for the driven element, director, and reflector. Performance characteristics indicate a forward gain of approximately 7.5 dBi and a front-to-back ratio of 18 dB at 50.125 MHz, according to _NEC2_ modeling. The antenna's compact size, with a boom length of 1.83 meters (6 feet), makes it suitable for portable operations or installations with limited space. Construction involves standard amateur radio workshop tools and materials, with a gamma match for impedance transformation to 50 Ohms. The design prioritizes ease of construction and repeatable performance for the 6-meter enthusiast.

Have you problem with your RG cables ? This page describes a smart antenna box using an RG-cathode for 3 antennas. The remote control needs just a simple wire and the GND for remote-control