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Cheap Yagi Antennas for VHF/UHF

Demonstrates the construction of a **multi-band HF mobile antenna** utilizing a modified CB whip antenna base. The resource details the process of stripping a commercial CB whip, winding a new helical coil with 0.7mm insulated copper wire, and identifying tapping points for various HF bands. It emphasizes the importance of a rugged, slim design for mobile operation, discussing mechanical length, power handling (up to 200 watts), and coil diameter considerations. The article includes a graphic illustrating the antenna's operational principle, where sections of the helical coil are shorted from bottom to top to maintain efficiency and high Q. The resource presents a practical approach to achieving **band switching** without an external tuner, by manually adjusting tapping points on the coil. It provides a table with reference lengths in centimeters from the feedpoint for 7 MHz (40m) through 28.7 MHz (10m), including WARC bands. The author details mounting techniques, suggesting a Diamond bracket for secure attachment to a vehicle trunk, and stresses the critical role of proper grounding for optimal performance. The design allows for operation on 75m and 80m bands by adding a 110mm steel whip.

The 160/80m coaxial receiving loop antennas are designed to enhance reception on the top bands while minimizing noise. These antennas are particularly beneficial for operators with limited space, as they can be constructed using lightweight materials, making them portable and easy to deploy. The standalone 80m loop has a diameter of approximately four feet, allowing for easy rotation and installation above existing VHF antennas. Over the years, many amateur radio operators have turned to loop antennas as a viable alternative to traditional beverage antennas. The design allows for significant noise reduction, especially when paired with a quality pre-amplifier. Experimentation with various configurations has led to the discovery that diamond-shaped loops provide optimal performance. Users have reported a noticeable improvement in signal quality, making these loops a valuable addition to any low-band DXing setup.

Frame antenna for 80 and 160 meters band

Building details of a VHF colinear antenna with 6 db gain

Author evaluated a custom-built passive AM loop antenna, achieving notable DX reception including KLBJ Austin (230 miles) and WWL New Orleans (700 miles). The antenna operates solely on resonant inductive coupling, enhancing weak signal reception without external amplification. This project illustrates how fundamental RF design—calculating inductance, capacitance, and Q factor—can significantly boost performance of consumer-grade radios. Detailed construction techniques, theoretical background, and optimization strategies for effective loop antenna design are presented for amateur and experimental use.

The page provides detailed plans and pictures of 80m and 160m antennas for both transmission and reception, emphasizing the importance of antenna farm on low bands. It discusses the differences between TX and RX antennas, the significance of signal-to-noise ratio, and the benefits of directional antennae. The author shares personal experiences and recommendations for successful operation on low bands.

Low noise, receive only coax loop antennas for 160 - 10 meters HF bands

The **Extended Double Zepp** (EDZ) antenna, a simple wire design, is presented as a means to achieve 3-4 dB of gain on 10 meters, with an overall length of just 43 feet. This resource, authored by WB3HUZ, details several gain antennas suitable for the 29 MHz AM segment, all modeled using EZNEC software at 30 feet above ground. Other designs include a compact rectangular loop, offering more gain than the EDZ and a lower take-off angle, and the **Lazy H**, a bidirectional antenna providing 6 dB gain, which is also workable on 20, 17, 15, and 12 meters. The Bisquare, a diamond-shaped open-top loop, is also featured, providing approximately 4 dB gain and requiring only a single support. These designs are primarily fed with ladder line or open-wire line to simplify matching, though a coax feed option for the EDZ is shown for 10-meter-only operation. The Lazy H, for instance, requires about 16 feet of open-wire line for its half-wavelength elements spaced a half-wavelength apart. An enhanced EDZ Lazy H variant is also discussed, achieving an additional 1-2 dB gain by extending element length to 1.28 wavelengths and increasing spacing to 0.64-0.75 wavelengths. The Bisquare, while primarily a 10-meter antenna, can be adapted for 20 meters by closing the top connection.

How to build a roofspace antennas and get them to work. Explains how to build an effective antenna in your roof. Very interesting if you don't have possibilities to setup an antenna in your roof.

High Performance Lightweight Antennas. The spider beam is a full size lightweight tribander yagi for 20/15/10m, made from fiberglass and wire. It has been specially developed as a highly efficient antenna for dx-pedition and portable use.

Basics by From Ian C. Purdie, VK2TIP

For radio amateurs considering homebrew antenna projects, this resource details several designs from WE6W, an experienced operator. It covers the construction and characteristics of a _160 Meter QRP Loop Antenna_ optimized for high voltage, along with standard and folded variations of the double bazooka antenna. The site also presents a unique Field Day antenna design and instructions for building a Sterba Curtain, a directional array known for its gain. Each design includes practical insights from the author's building experience. The author provides comparative data, such as the performance of a standard bazooka against a traditional dipole, offering real-world context for antenna selection. The Sterba Curtain section includes notes on its beamwidth and gain, crucial parameters for directional operation. These designs are suitable for hams looking to experiment with cost-effective, high-performance antennas for various bands and operating scenarios, from QRP on 160m to directional DXing with a Sterba Curtain, which can offer significant forward gain, often exceeding **10 dB**.

The Pfeiffer Maltese Quad Antenna System presents a unique approach to traditional quad antennas by utilizing a linear loading technique. This method effectively reduces the overall size of the antenna while maintaining its performance capabilities. Designed by Andrew Pfeiffer, the antenna's configuration resembles a Maltese cross, which not only enhances its structural integrity but also allows it to withstand challenging environmental conditions. This system is adaptable, offering various configurations from a 4-spreader Maltese Quad to a 16-spreader Maltese Quadruple-Cross, making it suitable for operators looking to optimize their setup without sacrificing efficiency. This antenna system is particularly versatile, covering multiple bands including 40, 20, 17, 12, and 10 meters. The design focuses on minimizing the physical footprint while ensuring effective signal transmission and reception. Amateur radio operators can benefit from the detailed plans available in the accompanying PDF, which outlines the construction process and specifications. Whether you're a seasoned DXer or a newcomer to the hobby, the Pfeiffer Maltese Quad Antenna System offers a practical solution for enhancing your station's capabilities.

Short guide to home made antennas for shortwave reception, in pdf format

Force 12 HF and VHF antennas, aluminim towers and masts for ham radio

Antenna Restrictions, Power Restrictions, RFI Problems, or Limited Space keeping you off the air?

Schema of a self made balun used to match randmon wire antennas, mainly for shortwave listening pourposes, in italian

How to construct a very small but efficient Antenna with PVC Plumbing tube and discarded fruit cans. - Just the thing to fit in a small space such as the house attic

Photos and comments on building an helical antenna for wifi

The J-Pole antenna is an omnidirectional antenna that can be used for base, mobile and field day stations. It does not need a ground plane, radials or a complicated matching system. The J-Pole can be cheaply, simply and quickly constructed using a variety of techniques, some of which are discussed in this article.

Lots of information on fabricating CB antennas

4 Element Cubical Quad, Yagis, LZA Circular Quad, Shrunken Quad , quarter wave, J-Pole, beam mounting , changing polarity

The page describes two types of 2 meter J-Pole antennas, one made of copper pipe and a roll-up J-pole made of TV twin lead, providing dimensions, components, and construction details. It is authored by Dr. Carl O. Jelinek N6VNG.

All these plans use the DK7ZB match

The website https://www.qsl.net/dl5dbm showcases homebrew projects related to KW, 2-meter, 6-meter, antennas, amplifiers, preamps, power supplies, and more. It provides information and resources for radio amateurs interested in DIY projects and experimentation.

A JavaScript to calculate the dimensions for a seven element Yagi-Uda Antenna

End-Fed Half-Wave Antenna for the 7 or 10 MHZ amateur bands intended to provide a very simple to erect yet effective portable QRP antenna.

Attic antennas can work better than you might think, some of mine work as well as their outside counterparts

Experience and practical use of magnetic loop antennas, by N0HC

Successful apartment operating starts with an evaluation of the location

This article describes how an effective ground system can be produced for a short vertical antenna.

Suggestions on finding RF ground when you live in an apartment and you want to setup an antenna

Two well performing 50 MHz antennas designed with W7EL EZNEC along to many other antenna projects and related articles

EH antenna for six meters band by IW0BZD

NGC is now distributor for COMET and MALDOL brand antenna products designed, manufactured in Japan. Distributor of DAIWA brand RF SWR/power meters and switching power supplies, antennas, test equipment, antenna analyzers and more

Homebrew VHF Yagi 50MHz 144MHz 432MHz 1296MHz 2320MHz 6M 2M 70CM 23CM 13CM Yagis

Small HF balcony antenna project

K9AY loop antenna installed at PA6Z Contest group. This is a receiving antennas for the low bands (160m, 80m and 40m). Include schematics and info on a building the control box, preamplifier and low-pass filter

Javascript for calculating the lengths of tubing to be used for the construction of a Super J-Pole in a collinear design

An on-line javascript calculator and quite a few pictures to show how to make a helix antenna.

A gamma match example

Pictures and plans to build 70 cm yagi antennas

KA1FSB loop calculator give you a quick overview of the feasibility of "squeezing" a loop into your available yard or apartment space. The easy calculator yields a reasonable approximation of dimensions, to within 5% over the amateur bands, using typical wire gauges ranging from 12-18 AWG.

Dipole antennas, unique broadband antennas, trap dipole antennas, coils, accessories for HF radio

How to build a beverage antenna. How to deploy a BOG antenna for your next SWL DX-ing activity. Give it a try and follow the orientation tips for this bi-directional antenna.

PKW Antennas for ham radio bands, Quads, delta loops, log periodics antennas for military and professional use by Ditta Martelli fabbrica italiana antenne

A multiband jpole antenna

Packing crate HF antenna

Demonstrates the construction of a **remote antenna tuner** utilizing a standard radio-controlled (RC) servo mechanism to adjust a variable capacitor. The design focuses on enabling remote tuning for narrow-bandwidth antennas, specifically mentioning frame and packing crate antennas, from within the shack. It covers the mechanical arrangement for integrating the servo with a capacitor and provides a circuit diagram for a control unit that generates the necessary 0.5mS to 1.5mS pulse-width modulation (PWM) signals to drive the servo's 180-degree rotation. This setup was successfully tested with up to 20 watts RF power without arcing or adverse effects on the servo, though tuning was performed at 1 watt for VSWR readings. The resource highlights the use of inexpensive, readily available components, such as Futaba servos, and details critical considerations like power supply decoupling with a 47uF capacitor to prevent unintended servo movement upon power-off. The system provides a practical solution for optimizing antenna performance for specific frequencies without manual adjustment at the antenna itself.