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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

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.

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

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

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.

Refurbishing a Cushcraft A3S, by George Szymanski, DU1GM

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

Amateur Radio - Antenna Zoning Book by Fred Hopengarten Telecommunications Lawyer

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.

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.

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.

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.

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.

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

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 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 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.

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

All about dipole antenna construction

A homemade 70cm handitenna made with a PVC pipe

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

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

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

Constructing a Compact Low Cost Sprinkler Valve Antenna Launcher

Hi-Z Antennas offers specialized high-impedance receiving systems, primarily focusing on phased vertical arrays for HF reception. Their product line includes preamplifiers designed for shortened vertical antennas, featuring optimized 15dB gain and array-matched characteristics. These components are engineered to enhance weak signal reception and improve signal-to-noise ratio across the HF spectrum. The company provides controllers for managing multiple vertical elements in a phased array configuration, enabling directional reception patterns. These systems are particularly effective for mitigating local noise and interference, a common challenge in urban and suburban operating environments. Specific offerings include solutions for 160-meter and 80-meter bands, addressing the unique requirements of low-band DXing. Technical details often reference components like the 2N3866 transistor in preamp designs and discuss concepts such as out-of-band attenuation. The focus remains on optimizing receiving antenna performance through impedance matching and active amplification, rather than transmit capabilities.

Loop Antenna Basics and Regulatory Compliance for Short-Range Radio

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

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

A magnetic loop antenna for the VHF band, featuring a high gain that can be compared to a quarter wave vertical antenna

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

W0IPL article on NVIS 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.

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.

Construct a compact, 20 meter rotatable dipole antenna of durable weather worthy components supported at a single point obviating the need for multiple supports and multiple support ropes crossing the yard.