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This is a short version, the final of the article describing how to build the Weather satellite 137 MHz horizontal V-dipole antenna.

This magnetic loop DIY site is ment to be an introduction into making DX high quality magnetic loop antennas that will beat any dipole

BIKELOOP is a VLF home made antenna. This antenna is a double magnetic loop composed by two orthogonal loops. This document describe how the prototype was built, the purpose is to give some construction hints to people who wants to try this kind of antenna. Mathematical and electrical details are described as well

This version of the 137MHz quadrifilar antenna for APT reception is an adaptation from Bill Sykes and Bob Cobey Taming the QFH which appeared in the March 1997 RIG magazine. This article contains detailed 3D pictures and models and detailed pictures.

The purpose of this construction is to enable the realization of an HF antenna called W3DZZ with minimal equipment and low cost. It allows traffic on the bands 3.5 / 7/14/21 and 28MHz.

A review of the 30 meter MonoGap Antenna. This review covers from the unboxing go the Gap product, the assembly of the elements, the test and tuning phase and a performance report during the years

A home made RDF 3 elements Yagi that can be used for fox hunting. The particularity of this antenna is that it can be folded, in order to save space while travelling. In Dutch.

This page describes an entirely simple, One-Knob matchbox that will match this antenna efficiently on 40, 30 and 20m, using a simple circuit that can be switched between series-resonant and parallel-resonant with just one banana jumper

A quarter wave vertical omni-directional antenna for 7 MHz. Formulas for dimensions in feet and meters are provided. Ideal radial angle is between 35° and 45°. Velocity factor (Vf) varies based on coax type.

The idea behind this antenna was to use multiple conductors in parallel to reduce the resistance losses in the antenna , and thereby improve the efficiency.For a given magnetic loop antenna, doubling the number of conductors from one to two will typically increase efficiency by about a factor of two. There is a limit, and beyond three or four conductors further increases are small, and may not be worth the bother.

The KGD antenna is an option for those with space restrictions. The idea behing this project is to provide a short dipole antenna for HF Bands and to allow operations on HF bands when its not possible to setup large antennas, using these short base loaded dipoles.

Spitfire Collinear Arrays for 160 meters band at UA2FW

Italian manufacturer and dealer of mobile cb radio antennas

A cavity backed antenna is a practical slot antenna tipically used in microwave applications

Experiments on vertical antennas for HF bands.

This article presents a comprehensive guide to constructing a multiband vertical wire antenna. The design features parallel wires for various bands, all connected to a single balun, ensuring ease of assembly and adjustment. Materials required include a fishing rod, PVC tubing, and inexpensive wire. The antenna is lightweight, cost-effective, and suitable for field use or as an additional home setup. Detailed instructions and diagrams are provided to facilitate successful construction and optimal performance across multiple frequencies.

A four position HF antenna switch with PC control

No matching adjustments needed. Directly perfect match to 50 Ohms using a remotely switched wideband transformer

A homemade simple and inexpensive portable antenna support, handy for quick trips to the field and other portable operations

Analysis of flag receiving antennas using MININEC with focus on relation of size and atenna height by VE6WZ

A homemade Quadri filar Helix Antenna project with detailed pictures that can inspire and guide you on building your onw QFH antenna sor 137 MHz.

This article provides details on building a 6 Meter J-Pole antenna using PVC pipe for an enclosure. This antenna uses flat 450 ohm Window Line for the tuning stub.

The antenna ground or earth system can be key to its operation whilst also being a key safety feature. This article is about grounding systems for antennas, covering different aspects of grounds made for antenna safety, or expressly for lightning or just to improve antenna performance, being ground an antenna component.

I wanted to mount an amateur radio antenna on my truck that was more permanent than the magnetic mount on I already had, but I had a few specific design requirements for the project.

This J-Pole is mounted on a fishing rod. The radiator L1 is an isolated copper-wire with a length of 281,5 cm while the quarter-wave matching sector L2 is made with 450-Ohm-Wireman-cable

High-performance rugged antennas and RF accessories such as magnetic mounts, RF coaxial gooseneck adapters, LNAs, BDCs, for law enforcment, military, maritime and video markets.

This type of antenna is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It’s a dipole fed off center with a 4:1 balun at the offset feed point. The antenna shown covers 80, 40, 20 and 10 meters. The formula can also be used to adjust the overall length to cover more or fewer bands and the resulting overall length. 160-10m, 80-10m or 40-10 meters depending on your available space. Other bands will require a tuner.

Construction tips of a basic wire antenna, the half wave dipole. Inverted V dipoles and effects of inverted v on radiation pattern.

A collection of 450 MHz Cheap Yagis that have proven great portable operations, back-packing and transmitter hunts, and are something inexpensive you can throw up in the attic for that weak repeater

An end fed antenna winder design that also contains the necessary matching toroid. This would be just the thing to throw in your backpack for portable operation.

A project about reversible unidirectional Beverage antennas plus a remote switching system conveniently controlled by the operator

Easy to use online Slim Jim antenna calculator. Input your frequency to automatically calculate the lengths of the different antenna parts.

If your goal is to obtain your DXCC award, here are a few tips that may help by k2ZS

Have you ever thought of setting up a portable HF station for an activity like the Field Day ?

Antennas custom made to your frequency of choice

Online antenna calculator for homemade double biquad antenna for UMTS 3G 4G WiMAX WiFi frequencies. Article includes also a simple biquad antenna for 4g

A review of the GAP Challenger DX Antenna that is not a traditional 1/4 wave vertical, but is a vertical dipole, this gives it several advantages over a standard 1/4 wave vertical, mainly the reduced number of radials, with excellent performances.

The Terminated End Fed Vee Antenna (TEFV) is a travelling wave antenna with constant current distribution. Unlike traditional resonant antennas, TEFV operates without standing waves, using a terminating resistor for broadband efficiency. With a combination of vertical and horizontal polarization, it offers wide bandwidth from 1.8 MHz to 30 MHz, eliminating the need for a tuner. Key components include a 9:1 unun transformer and a 500-ohm terminating resistor. Grounding and counterpoise enhance performance, and it can handle power losses of up to 30%. TEFV provides an effective, versatile antenna solution for amateur radio and broadcast applications.

How to solve RFI problems caused by the charge controller, which is a PWM type charge controller, that generates a lot of EMI interference

A multiple page article about assembling the antenna system, this section includes informations on constructing of the concrete tower base, starting from setting up correctly the foundations in relation to the antenna height.

A vertical antenna for 160 meters band based on the K6MM vertical with some enhancements and modifications on the main capacitance hat

There are quite a few variants of the design accompanied with many opinions on the effectiveness of the antenna. This page features links to some similar projects and a homebrewed personalized version of this portable antenna tuner

Undestanding and measuring SWR, Standing Wave Ratio in antenna feed lines. This article also introduce basic concepts and usage guidelines of amateur radio antenna tuners

I used a FT 240-43 for much more power, not needed but beter safe than sorry. 150 Watt continious, 300 Watt PEP SSB, 90 Watt Digimodes 10 Mhz, 18 Mhz, 24 Mhz Very easy to build design and a good antenna for people who don't have much space for big towers or long wires This design is from Hans - PE1RNU

This project was originally developed by Markus VE7CA A Portable 2-Element Triband Yagi - PDF Article

A basic YAGI UDA online antenna calculator, accept as input frequency, number of elements, diameter of parasitic element and boom diameter. This online calculator will generate a basic design data including each element length and spacing.

F5NPV introduces a variant of the W8JK antenna design, employing the MOXON principle. With extended monopoles, it outperforms the Open-Folded W8JK, yielding a 1dbd gain improvement, enhanced performance on 30m and 10m bands, bi-directionality, and lower side attenuation. The design's focus on higher radiation impedance results in increased antenna efficiency and reduced losses. Despite these improvements, the bill of materials remains unchanged.

This is a simple half wave antenna for 70 cm band, made using the jpole design.

Building A Full-Wave Quad Loop Antenna for 6 Meters. This is an easy antenna to build and the materials cost about $15-20. It exhibits 1.8dB gain over a 1/2-wave dipole. Using an open-wire parallel feedline (commonly called ladder line) with an antenna tuner, it tunes up on the 10m band as a 5/8-wave loop as well

Dipole antennas, vertical half-wave dipole antennas with impedence tranformes that can be used for portable operations. Some well worn antenna configurations are the easiest and loudest lash-ups you can try.