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Performance chart of VHF antennas in a stacked array

Designing and constructing portable wire antennas for HF operations, this resource explores several configurations including the _foldback dipole_ for space-constrained setups and an inductively shortened dual-band dipole for 20m and 40m. It details the calculation of inductance for shortened elements, providing a Visual Basic 6.0 program screenshot that illustrates determining coil parameters like turns and length for a **25.5 uH** inductor. The document emphasizes practical considerations such as adjusting wire lengths for optimal SWR, noting that a dual-band dipole achieved SWR below 2:1 on both 20m and 40m, with careful adjustment bringing it under 1.5:1. Further, the resource describes a half-wave antenna matched with a coaxial stub, a method often referred to as the _Fuchskreis_ in German amateur radio circles, to transform the high feedpoint impedance to 50 Ohms. This monoband solution, for a 20m application, uses a stub length of **2.98m** (0.216 lambda multiplied by coax velocity factor) and a shorted stub of approximately 48cm. The coaxial stub design is highlighted for its resilience to ground proximity, allowing it to be rolled up or laid on the ground with minimal SWR impact, making it highly suitable for portable QRP operations.

KA7OEI article on homebrewing Yagi UDA antennas with practical suggestions and designing notes.

The Speaky HF SSB transceiver and other homebrew projects Homebrew of radio equipment, antennas, tuner, etc.

Magnetic Loop Antennas for The Radio Operator with Limited Space, a two part series of articles on how to construct a magnetic loop antenna, including directions on selecting high voltage tuning capacitor

Antenna tuners are crucial for matching the impedance of antennas to the 50 ohm output impedance of transmitters. The _LDG Z-11 Pro_ is an automatic antenna tuner designed to handle up to 125 watts, making it suitable for a wide range of amateur radio applications. Its compact form factor allows it to pair well with transceivers like the _FT-857D_, providing a portable solution for operators who frequently change locations or setups. The tuner covers the 80 through 6 meter bands, offering a broad impedance match capability. Although it struggles with some loads, it performs well with typical ham antennas, even managing to load an 80 meter dipole on 6 meters. One of the standout features of the _Z-11 Pro_ is its 8000 memory slots, which enable it to remember successful matches and quickly retune when revisiting frequencies. This memory function significantly reduces tuning time, often to less than half a second. The unit is well-constructed, with improved pushbuttons and a sturdy metal case that offers good shielding. However, users should be aware of potential RFI issues and the lack of a power switch, which requires disconnecting the power cord to turn off the unit completely. Overall, the _LDG Z-11 Pro_ is a user-friendly and cost-effective tuner, offering advanced features that enhance its utility in various amateur radio setups.

Dipole, inverted V, full wave loop and grond plane antenna quick reference plans

An effective multiband HF Vertical antenna, used as remote station antenna. Pictures and review of this vertical HF antenna by VK5SW

T-Match Network Antenna Tuner for a wide range of complex antenna loads between 1.8 and 30Mhz at moderate power levels by VK6YSF

Types of coax-cable with rf attenuator calculator, line loss calculator form includes an antenna gain calculator. This coax loss calculator can help you on choosing the right cable for your antenna sysmte.

With all the wire you have out, you may run into a problem with static buildup on the antennas. This static may try to make its way into your receiver, causing you major problems and damage that can run into a lot of money.

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

Building EH Antennas at Gemran radio club station house, by Matthias DH4FAW

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.

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

Modeling small 160 meter antennas, with a focus on the vertical H antenna

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.

Aduino-based Amateur Radio Antenna Rotator Controller that can emulate the Yaesu GS-232A or GS-232B interface by K3NG

Tips on winding wire coils used as inductive loads, traps, band-pass filters, are implemented in a number of amateur radio projects especially antenna projects

Refurbishing a Cushcraft A3S, by George Szymanski, DU1GM

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

A Slim Jim Antenna project

Article by N6LF on a top band vertical antenna array system

Antennas, Standard Delay Line Systems, Crossfire Phasing or Hybrids

Amateur Radio - Antenna Zoning Book by Fred Hopengarten Telecommunications Lawyer

Review of Cushcraft MA-5B multiband Antenna after some days of usage.

Design of a 40 meter Vertical antenna

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

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.

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.

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

Cushcraft A3S HF antenna 1:1 balun repair.

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.

A multi band portable link dipole antenna for 20 30 and 40 meters band

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.

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

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

This circuit enables fair copy of strong 444 MHz signals, off a local repeater, using a 2m rig and a 1/4λ 70 cm indoor ground plane antenna.

Electrically shortened dipole antennas, article by Mark Connelly, WA1ION

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

Quad antenna homebrewing, mechanical considerations by IZ7ATH

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

Theory of the ferrite rod antenna

Some Notes on the Slim Jim Antenna by Dave Coomber M0UXB

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.

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

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

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

The early 20th century saw significant advancements in wireless communication, culminating in the first successful transatlantic radio signal. This historical account details Guglielmo Marconi's pioneering efforts, from his initial experiments with electromagnetic waves to his patented wireless system in 1900. It describes the technical challenges of long-distance radio transmission, particularly the prevailing belief that radio waves would be lost due to the Earth's curvature over vast distances. On December 12, 1901, Marconi established a receiving station in Newfoundland, Canada, utilizing a _coherer_ and balloons to elevate the antenna. Signals, consisting of the Morse code letter "S" (pip-pip-pip), were transmitted from Poldhu, Cornwall, England. The successful reception of these faint but distinct signals across **1,700 miles** confirmed Marconi's theories, marking an epoch in communication history. This achievement demonstrated the viability of global wireless communication, paving the way for future developments in radio technology.

A homemade 70cm handitenna made with a PVC pipe