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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.

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

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.

ARRL article on random wire antenna, simple antennas that can be tuned for every band, excellent solution for field day operations

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

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

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 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

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

A four element 2 meter quad antenna project

The Yagi-Uda antenna, information on basic design, project and measure of Yagi-Uda antenna, include free repository/sample of beam antenna.

A remotely tuned 80m to 10m wire vertical antenna

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

An interesting project of the popular IW3HEV antenna analyzer in and embedded solution by PA3CKR.

Single Coax Feed to Multi-Band Copper Cactus Antenna.

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

Article on mobile antenna mounting methods by Firestik

A 27-28 Mhz quad loop antenna by Bernard Mourot F6BCU in french

Homebrew a 2 meter square dipole antenna

Dimensions for the inverted V antenna from 160 to 2 meters by N6JSX

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

This online microstrip patch antenna calculator determines the length and width of a microstrip patch antenna for a given frequency

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.

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

Demonstrates the construction of a 144 MHz turnstile antenna, detailing its design for omnidirectional, horizontally polarized VHF operation. The resource outlines the physical dimensions and materials required, including specific lengths for the radiating elements and the use of _RG-58_ coaxial cable for phasing. It covers the assembly process, emphasizing the critical spacing and connection points to achieve the desired radiation pattern and impedance matching for the _2-meter band_. The article presents measured _SWR_ performance across the 144-146 MHz segment, showing a low SWR of 1.2:1 at 144.5 MHz, which is suitable for general VHF use. It compares the turnstile's performance to a 9-element Yagi, noting the turnstile's advantage in providing consistent signal strength from all directions without requiring a rotator. Practical application for local FM simplex and repeater operations is implied, offering a simple yet effective antenna solution for fixed or portable stations.

About longwire antennas, technically to be a true longwire an antenna needs to be at least one wavelength long, but common use of the term by Hams is for any random wire length that is end fed.

A nice loop antenna project for 28 MHz with schematic diagram, construction details and a complete video instruction

A 40 meter NVIS beam antenna by W4NVK

A Unique VHF Antenna with gain over a J-Pole Jose I. Calderon, DU1ANV

A project of a 5 Antennas Relay Switch Box, all Switches & Relays have both contacts wired in parallel to improve reliability of operation, to prevent static build up, when an antenna is not in use the feeder coax is grounded.

Optimizing performances of the end-fed antennas QRP quarterly article

All types of Military Antennas, Law Enforcement Antennas, Mobile Radio Antennas, GPS Antennas, Satellite Antennas, WLAN/Wi-Fi/WiMax Antennas, Cell Phones, TV, HDTV Antennas available and sold

A 915 MHz four bay j-pole antenna plan

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

Deploying robust antenna infrastructure for both fixed and portable operations often requires specialized support structures capable of withstanding environmental stresses while providing optimal radiating element placement. SMC offers a range of solutions, including pneumatic masts and push-up masts, designed to facilitate rapid deployment and reliable long-term support for various antenna types. Their product line encompasses antenna mounts, poles, and complete antenna systems, addressing the critical need for stable and efficient RF communication. The company's offerings extend to HF antennas, including dipoles and _NVIS_ (Near Vertical Incidence Skywave) antennas, which are crucial for short-range regional communications on bands like 80m and 40m. These systems are engineered for durability and performance, ensuring signal integrity across diverse operating conditions. With over **65 years** of experience, SMC has established itself as a global manufacturer in this niche. Their product portfolio also includes antenna support towers, catering to more permanent installations requiring significant height and load capacity for multiple arrays.

G3TXQ study on coaxial cable demonstrate that it can reduce an element's length by something approaching the Velocity Factor of the cable

VK3YE magnetic loop antenna plan that cover 7 Mhz to 20 Mhz and shortening loop can work on 21 Mhz.

An excellently presented article on the design and construction of a medium wave DX Antenna

A delta loop antenna for the 4 meter band by GW7AAV

Build an effective dipole antenna that needs much less space by adding two loading coils. This online calculator tells you how.

A simple coax dipole antenna for 144 MHz by 9A7PJT

A novel approach to contruction of a gamma match.

Iulian Rosu YO3DAC / VA3IUL wire ham radio antenna panoramic with sample drawings

US Antenna manufacturer offering base and mobile antennas for 2 meter, 1.25 meter and 70 cm Amateur Radio GMRS and MURS Citizens Band Radio VHF and UHF Business Band Radio HF, VHF and UHF Scanning

High Gain Wi-fi Helical Antenna by AB9IL

The resource presents a detailed schematic for constructing a dual-band vertical antenna, specifically designed for operation on the 2-meter and 70-centimeter amateur radio bands. It illustrates the physical layout, critical dimensions, and component placement necessary for successful replication. Key elements such as the radiating elements, phasing sections, and feed point are clearly depicted, providing a visual guide for radio amateurs undertaking a homebrew antenna project. The diagram specifies the lengths for the VHF and UHF sections, indicating how these elements are integrated to achieve dual-band functionality from a single coaxial feedline. It also implies the use of common materials readily available to most experimenters, focusing on simplicity and effectiveness in its design. The visual format of a GIF image ensures direct access to the construction details without requiring extensive textual interpretation. This schematic serves as a practical reference for hams interested in building a compact, efficient vertical antenna for local and regional FM communications, offering a proven design for immediate implementation.

An RSGB article on end-fed wire antennas and the W3EDP alternative.

Optimization tests of the W3EDP multi-band HF wire antenna a popular aerial among QRP enthusiasts because it is light weight and cheap.