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A study on 20m antennas by Kenny Silverman, K2KW

A 70cm ground plane antenna made with a 90cm of 1mm silver steel rod

Constructing a directional antenna for the 6-meter band (50 MHz) can significantly improve signal strength and reduce QRM during local ragchews or **Field Day** operations. This project details the assembly of a Moxon rectangle antenna, known for its compact size and respectable gain, making it a practical choice for portable or fixed station use on the magic band. The design utilizes readily available materials such as 14 AWG copper wire for the radiating elements and PVC pipe for the frame, ensuring an inexpensive build. The article provides specific dimensions and construction steps, allowing radio amateurs to replicate the antenna with confidence. It emphasizes achieving a low **SWR** across a bandwidth exceeding 1 MHz, crucial for efficient power transfer from the transceiver. Performance characteristics include a reported 5.5 dBi gain and a front-to-back ratio of 20 dB, offering effective directivity. The project also highlights the antenna's suitability for Field Day, where quick deployment and reliable performance are paramount for maximizing contacts.

A different implementation of the G7FEK HF multiband antenna with some adjustments and modifications

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

Essentially, a choke balun is designed to 'divorce' your antenna from the feed line. if your feed line is coaxial cable then you don't want it to be part of your antenna. you want to be able to deliver all your power to the radiator itself, i.e. 'the antenna'. a choke balun does this admirably

A considerably shortened Magnetic Loop antenna with performance of a single conductor text book magnetic loop.

1:49 UNUN using two stacked FT240-43 cores for end fed halfwave antenna. To match the end fed half wave antenna to the coaxial feeder, it is necessary to have a matching network or transmission line transformer.

A 2m band Moxon antenna design is presented, centered at 145.2 MHz, with dimensions derived from Moxgen software. The design features a calculated 6 dBi gain, an 80-degree beamwidth, and an impressive 43 dB front-to-back ratio with minimal back lobes, concentrating RF energy in the forward direction. The antenna is balanced to 50 Ohms, facilitating direct feed. SWR sweep data from 144 MHz to 146 MHz demonstrates a near 1:1 SWR at the center frequency, maintaining healthy SWR values across the entire 2m amateur band. This performance is comparable to a 3-element Yagi, yet the Moxon offers advantages in compact size and ease of mast mounting, making it suitable for various operating environments.

Horn Antennas theory and principles

A project for a ground mounted 4 square antenna by DM9EE

A review of all possible receiving antennas for top band 160 meters

Comment on W5DXP 2011 coil measurement experiment

Converting a little Radio Shack CB mobile magnet mount antenna to a VHF ham radio antenna

Ultra portable and lightweight folding beam antennas based on G3TXQ design

A Microvert antenna by KD5RVX based on the original microvert concept by DL7PE. PDF includes a 20 foot portable PVC tower project

Some notes on double-shielded coaxial cable

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

HF VHF UHF antenna ideas to be used for field days. All antennas are quick to set up and take down and offer proven performance and flexibility. Presentation offered by Mahoning Country ARES

Homebrewing portable antennas for field day operations

How manage and quantify ground loss in vertically-polarized antennas by VE3VN

A helically wound vertical antenna experiment. 14 meter of wire wounded on a 8 meter fishing pole with 4 elevated radials

N5KGL interesting article on portable antennas. Greg report his experience on using several types of portable antennas.

WA1ION article on beverage and ewe antennas

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.

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.

The ZR6YY Antenna for 6m by Maurius ZR6YY revisited by YT1VP

In this article you can find solutions to the problem of keeping your ham radio antennas hidden from the CCR Police

SPIDERBEAM.US is the exclusive distributor of Spiderbeam antennas, and online shop for USA & CANADA

This article is about a 4 element yagi VHF antenna designed to be easy to be assembled and suited for portable operations

G0KYA MMANA-GAL presentation and samples

NRSC AM bandwidth measurements with the loop antenna

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

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

Design a 50MHz long-yagi antenna by PA3FGA

Understanding Amateur Radio NVIS Antennas and Propagation

Design for a quarter wave vertical antenna, for the top band in use at V31YN

A page describing how to home made a custom 9:1 balun for a common portable wire antenna. The author suggest to use 4C65 or FT140-61 toroids instead of the common Amidon T200-2

Article about an end-fed anntenna for the 17 and 12 WARC Bands. 30 meters is not included in this project. This antenna includes a 14 windings unun impedance transformer using a FT-140-43 ferrite toroid, that should be enought for a 100W PEP.

4 Square K9AY Array project for 80 and 40 meters band

A 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

A Programming-Free Automatic Arduino Antenna Switch project published on NCJ

This simple project, based on the orginal CobWebb-Antenna model, is about an horizontally polarized, omi-directional antenna for the six meter band.

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

A homemade pneumatic projectile launcher project

Setting up a ZZ Wave antenna, a dual band loop antenna covering 80 and 40 meters.

A delta loop antenna for 20 meters band designed with MMana with a tuning system made in a classic stub configuration

Antennas, Transmission Lines, Tuners - Myths, Mysteries and Qualifiers By Don Wilhelm W3FPR

An article and buyers guide about antenna anlyzers, undestanding differences among popular RF analyzers in the market

A VHF UHF mobile operation setup with APRS tracking by wd6cmu