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The page discusses the concept of a 2-element Parasitic Ground Plane antenna for the 40-meter band. It includes a conversation between amateur radio operators discussing modeling results and design considerations for the antenna. The author shares insights on radial configurations and the impact on antenna efficiency and pattern.

Amateur Radio - Antenna Zoning Book by Fred Hopengarten Telecommunications Lawyer

My Top Five Backyard Multi-Band Wire HF Antennas. A selection of the top 5 HF wire antennas for the backyard and for multi-band operation

Photo construction manual of a portable antenna made with two heavy duty whips by buddipole. In this article has been implemented a 50 MHz portable dipole.

Design of a 40 meter Vertical antenna

A general article on CMC, common mode choke include a description and tipical usage.

Cushcraft A3S HF antenna 1:1 balun repair.

Small antenna, what causes loss and how to increase radiation resistance in small antennas., A description of loss and radiation resistance.

The broad band hexagonal beam (hexbeam) designed by G3TXQ and built by K4KIO

With the view to establish a quick and easy multi-band antenna deployment for portable and camping operations a simple long wire antenna with an earth or earth plus counterpoise arrangement with a 9:1 voltage unun including a tuner or simply with a tuner is one possible solution. With the 9:1 voltage unun and wire lengths suggested in the below tables the antenna should present non extreme impedances for all HF amateur band frequencies. This page is far from complete and represents the ongoing investigation into this type of antenna. Experiments to date seem to have raised more questions than obvious answers.

Schematic diagram and description of a magnetic loop antenna that works from 10 to 20 meters band, made from junk

Electrically shortened dipole antennas, article by Mark Connelly, WA1ION

Antennas for Broadcasters, PSI manufactures a complete range of slot antennas for UHF television broadcasting

G4ILO compares popular antennas for 2 metre band handhelds so as to see how much you lose using a small inconspicuous antenna or how much you gain by using a long antenna.

Find out how much to adjust the length of a quarter wave whip or a half wave dipole rather than the outright cut-and-try method.

Quad antenna homebrewing, mechanical considerations by IZ7ATH

The 160 meter ground plane is constructed from #10 stranded insulated wire available in most hardware stores. The feedpoints / tiepoints use PVC pipe T-sections Article by W1TR

Build the Slim JIM Antenna, a unique VHF Antenna with gain over a J-Pole Jose I. Calderon, DU1ANV

Theory of the ferrite rod antenna

Some Notes on the Slim Jim Antenna by Dave Coomber M0UXB

A comparative article on performance differences between Slim Jim antennas versus J-Pole antennas

All about dipole antenna construction

The AB2RA bowtie 80 meter antenna includes also a 40 meter dipole

Antennas for asset tracking, navigation and remote monitoring GPS, GSM, GPS/GSM, Satellite Radio, WLAN

The resource details the construction of a multiband trap-style Inverted-V antenna designed for operation on 3.5 MHz, 7 MHz, 14 MHz, 21 MHz, and 28 MHz. It presents specific winding data for the traps, including the number of turns, wire gauge, and coil former dimensions, crucial for achieving resonance on the target bands. The document provides a parts list and a diagram illustrating the antenna's physical layout and trap placement. It outlines the process for building the traps using PVC pipe formers and specifies the required capacitor values for each trap. The design emphasizes a practical approach to achieving multiband operation with a single feedline, a common goal for HF operators with limited space. The document includes a table with antenna segment lengths for each band, allowing for precise replication of the design. It also offers insights into tuning and adjustment, ensuring the antenna performs optimally across the designated amateur radio bands.

Building a Windom HF Antenna. A PDF file presentation about homebrewing a windom antenna for the HF bands with formulas for 40 and 80 meters bands and step by step guide on making a 4:1 balun to feed the antenna.

The vertical Double-Zepp 2x7 m is a very simple, effective 8-Band-antenna. The end of the Dipol must be 5-10 m above the ground

An antenna for shortwave radio broadcasting consisting of rows and columns of dipoles, is a high gain directional antenna, designed for medium and long range communications.

This is another alternative home-brew center connector for a dipole. The parts used are common PVC accesories found at the home supply store.

A homemade 70cm handitenna made with a PVC pipe

Constructing a Compact Low Cost Sprinkler Valve Antenna Launcher

Useful hints & tips on building a 10 and 17 meter Moxon Antenna

Testing performances of indoor antenna. A comparison of a magnetic loop antenna vs a classic wire dipole done using wsprlite on 30 meters band.

Loop Antenna Basics and Regulatory Compliance for Short-Range Radio

High impedance amplifiers for shortened vertical antennas, Array matched and Optimized 15dB Preamplifier

W0IPL article on NVIS Antenna

Magnetic Loop Antenna for 20/15m with Remote Tuning by George Szymanski

This antenna article is geared towards new Hams and antenna builders looking for a very inexpensive 6 band antenna that can be efficiently fed with 50 ohm coax without a tune

Refurbishing a Cushcraft A3S, by George Szymanski, DU1GM

Since they were first described by the French mathematician Benoit Mandelbrot in the mid-1970s, repeating geometric figures known as fractals have fascinated computer scientists, mathematicians and graphic artists.

A directional active loop receiving antenna system by J A Lambert G3FNZ article published on Radcom in november 1982

How to build a QFH (Quadrifilar Helix Antenna) to download images from weather satellites. A complete tutorial on assembling QFH antenna at home with simple and common tools

The HyGain LJ-153BA a monoband 3 element Yagi, designed for the 15 m band 21.00 - 21.45 MHz

Discussion at eham about wire size used in wire antennas, and how it affects the gain of the antenna

A 38-foot Tristao Tower, similar to the U.S. Tower HDX538, was installed twice by the author, first in 1980 and then reinstalled in 1989. The resource details the challenges of self-performing heavy construction tasks like breaking concrete and digging a 3' x 3' x 6' deep footing, contrasting it with hiring professionals for the second installation. It highlights the financial and physical costs associated with DIY tower foundation work, noting a rebar cage cost of $65 in 1980 versus $150-$175 today, and the expense of tools for bending rebar. The content emphasizes the critical importance of obtaining building permits, recounting how a permit in Buena Park, California, nullified a neighbor's complaint about TVI. It also discusses the necessity of adhering to local building codes, such as the 1975 UBC and the subsequent 1985 UBC recertification requirement, which reduced the allowed antenna wind loading from 30 square feet to 20 square feet for the author's _KT34A_ Yagi. The footing depth also increased from 6 feet to 6.5 feet under the newer code. Practical advice includes hiring licensed contractors for specialized work, delaying antenna installation for a month after raising the tower, and verifying buried utilities before any excavation. The author provides specific examples of utility location services like _DigAlert_ in California, underscoring the legal and safety implications of neglecting this step. The narrative is grounded in personal experience, offering a realistic perspective on tower projects.

Description and simulation of two types of rhombic antennas, using the software 4Nec2: the simple bi-directional and the terminated directional rhombic antenna

Based on a simple project based on a 2 elements Yagi for 20m band, and then becomed a triband yagi with a open-sleeve feed system

Experiences with Loop antennas at G3YMC include some loop antenna tests and theory by G3LHZ

Here are 10 tips and truisms that every ham should know about antennas, by W20QI

A ten element ultra-lightweight yagi beam antenna for 144 MHz based on YU7EF design concept